Dr Don
by Lokrume
Summary: Donnie is determined to find a retro-mutagen, but doesn't notice that one of his experiments is starting to affect his brain. What would Donatello be with twice the intellect, but with a fading ability to tell right from wrong? And how far is he willing to go in order to create a retro-mutagen, or simply satisfy his curiosity…? /Nickelodeon. See Author's Note for details.
1. Prologue

_Note: These events take place during season 2, somewhere after "The Good, the Bad, and Casey Jones" and before "The lonely mutation of Baxter Stockman"._

**Author's Note:** I'd love to see this side of Donatello in the 2012-version, but that's probably never going to happen… Thank god for fanfics! ;D

This is a somewhat different "Dark Donatello"-story in the regard that he's not exactly evil. As mentioned in the synopsis, he's still pretty much the same dorky, lovable turtle we know from the show. But with a somewhat screwed up sense of morality... Especially when it comes to whether you can or cannot use family members for your experiments.

**This story contains:** Whump, creepiness, needles, blood, humor, angst, light fluff, some Apritello, and Casey Jones.

**You will NOT find:** Character death, sexual themes, or explicit gore.

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><p><span>Prologue<span>

Donnie's hands were shaking slightly as he patiently tried to add the exact right amount of yellow liquid to the content on a petri-dish. His eyes were staring blearily in front of him, and he found it a hard to focus at the task at hand. He somehow mustered enough determination to successfully mix the components without a problem.

The hour was clearly late, and the scientist looked like he should have gone to bed a long time ago.

The tall turtle made a pleased smile over his accomplishment and put the dish in an incubator. He hoped that this batch would show more progress than the last one. Or any of the 37 he had tried so far… Donnie was just about to stow away the bottles of chemicals he'd been experimenting with, but hesitated. He tapped his chin with a thoughtful expression as if he was trying to recall something. His eyes slowly widened in panic and he darted over to a burning hotplate, where a jar of mutagen was boiling merrily. Donnie swiftly turned off the plate and quickly moved the jar away from the heat source, careful to not breathe in the fumes. He made a relieved sigh as he put down the jar on the desk instead, and then went back to his various bottles.

"Alright," he stated to himself, and rubbed the back of his neck. "Unless I accidentally wanna end up mixing water with potassium, I should probably call it a night now."

He had barely finished the sentence when he stopped himself and took one last look on his experiments. He stared at the jar of cooling mutagen in silence.

"... Maybe just one more try," he concluded, and put the jar back on the hotplate again. "One more test, and then I can finally leave this behind me and get a few hours of well-earned sleep."

Donnie glanced at the clock at the corner of the computer screen. It politely informed him that it was 5:15 in the morning.

"… Or maybe a few minutes nap," he sighed, and shook his head in annoyance. "Why do I keep doing this to myself...!"

Donnie put on a mask and added some kind of blue liquid to the boiling mutagen, leaning away from it to protect himself from the fumes. Or a potential explosion. The mutagen seemed to react somewhat to the substance, making Donnie watch the mixture in excitement.

In the next moment, the mutagen gave up a tiny cloud of smoke with a squeaky, farting sound. Donnie's shoulders slumped as he looked at the experiment with the eyes of a disappointed parent. He sighed, tossed the mask aside, and then started writing in a journal on his desk. The book was filled with mathematical formulas, scientific terms, and sketches of chemical symbols. Though, some of the sketches were obviously of a more personal nature, like a drawing of a yellow spring flower with tiny hearts circling around it.

"So far, no further progress on the retro-mutagen experiments..." he mumbled to himself as his hand moved over the pages, with the swiftness of someone who didn't intend his words to be read by anyone but himself. "I did however discover some rather unusual reactions when the mutagen is mixed with substances containing high levels of sodium chloride, but nothing that appears to be substantial in my search for properties that can-"

He observed the words while tapping the pencil on his chin with a critical look. He sighed bitterly, and replaced the last sentence.

"It farts in contact with salt." he clarified with a tired look, and kept scribbling. "At this point, I'm getting increasingly concerned whether I'll be able to find an efficient way of creating retro-mutagen in... before I..."

He made a big yawn and rested his chin in his free hand. The other one kept writing in the journal, almost absentmindedly. His focus was slipping with every word.

"I need to learn more about the mutagen. If I could just get my hands on some new information, I might be able to come up with more ideas. At this stage, anything would be helpful, really... But for that to happen, I'll most likely need another Kraang flashlight... Flash-drive. Another Kraang flash-drive. To drive...No, to get new information. To get some... more ideas for... research, and...stuff..."

His head gently slipped down from its propped up position, and heavily hit the desk. But Donnie didn't wake up from the impact. Instead, he was snoring lightly on top of his journal, with his arms acting as skinny pillows. He mumbled something in his sleep which, even if someone would have heard him, probably wouldn't make a lot of sense.

The hotplate was still burning. The fumes of the mutagen steadily rolled out from the jar, like toxic waves. It didn't take long until Donnie was sleeping in the middle of a greenish fog, inhaling it soundly in his inattentive slumber.

. . .


	2. Chapter 1: Try not to scream

**Author's Note: **I hope the prologue didn't bore you. I promise you, things will escalate quite rapidly from here on. ;) And please keep an eye out for any goofy grammar or just plain weird English. By fixing the problems, more people can enjoy the story, and it will also improve my writing. So let me know if you find anything odd in the text. :)

**TRIVIA:** Not so "fun" fact: I had a panic attack while writing this thing. A full blown "OMG I'm dying and I'm gonna die and there's no tomorrow"-moment. I'm not sure why it happened. I've never had one before. But now I can't look at this story without thinking about it. Hopefully, none of you who reads this will ever have to experience what that feels like. But if you have: Here's a cookie and a hug. ^^

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><p><strong>Chapter 1: <strong>"**Try not to scream"**

Leo's smile dropped as he left the dojo, and saw Raph sitting in front of the TV. His brother turned around at Leo's presence and gave him a victorious smile. Or a mocking one. Raph rarely made any difference between the two.

"Of course," Leo stated unimpressed as he walked up to the couch. "I told you that I wanted the TV after practice, so naturally you had to take it."

"And I told you that you could have it if you beat me," Raph informed him simply, and waved the TV remote at his brother with a grin. "Look how that turned out."

"I never agreed to that bet!" Leo exclaimed, with an upset gesture.

"Never said you had to." Raph shrugged.

Leo clenched his fists and glared at Raph. The other turtle grinned and eagerly took this as a challenge. He tossed the remote so that it ended up right between them. Leo looked from the discarded remote to Raph. His brother was smiling in a plotting way as he took on a fighting position, like a fox ready to catch a vole.

"Go on, take it," Raph coaxed, his legs like coiled springs, ready to jump at slightest of movement. "I'm up for a second round. Who knows? Maybe you won't lose horribly this time."

"Probably not," Leo stated, and calmly sat down in the couch where he picked up an old comic book instead. Without dignifying his brother or the remote a look. "Since I'm not gonna fight you."

"What the…?" Raph said with an upset look, and turned to Leo as if he had just insulted his mother. "Oh come on! You can't give me a walkover. I was just getting started here!"

"We just _finished_ in the dojo," Leo explained, with a raised eyebrow at the quarrelsome turtle. "We've just had a backbreaking training session, and you _still_ need to blow off steam? How can you not be tired of this?"

"Don't know," Raph answered, and folded his arms with a provocative look. "Were you guys wimpier than usual?"

"I'm _not_ gonna fight you over the TV," Leo stated, ignoring the insult and flipped through the pages of the comic. He was just about to read it when he felt something hard hit him in the head and land in his lap. He picked up the remote control with a narrow look at his brother, who had sat down in the couch next to him and seemed too busy watching a commercial about air conditioners.

"Sometimes, I have my doubts that we are the same age," Leo thought out loud.

"Sometimes I doubt we're related," Raph pointed out casually.

Leo rolled his eyes at the comment, but then looked down at the remote in his lap and picked it up with a pleased smile. He aimed it at the TV to switch the channel, but his expression changed when the remote didn't want to comply with the order. He tried the buttons several times and then gave Raph an annoyed glare.

"Just so you know, this just proved my theory," he told him.

"What did?" Raph asked, with a frown.

Leo didn't elaborate. Instead, he bitterly opened the battery hatch and showed his brother the empty compartment.

"Don't look at me," Raph said, and shook his head. "My kind of pranks has more carnage to them. This kind of immaturity is more Mikey's thing."

"Wait, where is Mikey, by the way?" Leo suddenly asked and looked around, as if he expected the youngest turtle to have been quietly observing them the whole time. He felt ridiculous for even considering the idea.

"Why don't you ask the B-team's better half?" Raph suggested, and turned his attention back to the TV.

"You mean Mr Distracted?" Leo said, with a crooked smile. "I doubt Donnie knows where he is. He could barely keep an eye on Mikey during training. Which is quite an achievement considering that his nunchuks were in his face most of the time..."

"So you noticed it too, huh?" Raph asked, with a glance at Leo and chuckled. "Man, he really didn't put up much of a fight today. I think I still can see his face in my knuckles."

"You could have gone a little easier on him," Leo told him, knowing that his words fell upon deaf ears. "But you're right. Donnie did _not_ have his head in the game today. I thought it was odd that Sensei called off the training so early, but now it kinda makes sense…"

"Yeah, maybe he realized that when one of your students is turning as purple as his bandana, it's probably a good time to quit," Raph said, with an amused grin.

"When I think about it, I've barely even seen Donnie today," Leo admitted with a thoughtful expression. "Not before the training anyway."

"I have," Raph shared, with an indifferent look. "Those twelve seconds at lunch when he grabbed the toaster and a couple of forks. Not food, just the toaster and _forks_."

"…Should we keep a better track of what that guy does in his lab?" Leo said, with an almost worried look. "He's been more antisocial than usual today, and we have literally no idea what he's doing. One second we only see him when we train or eat, and the next second he has made smoke bombs, t-phones, go-karts-"

"Patrol buggies," Raph corrected him, just to annoy.

"What I'm trying to say is that he's been cooped up in the lab for too long," Leo said and got up on his feet. "I know that we need the retro-mutagen, but I think _he_ needs to get away from all that work. It can't be good for him."

"Yeah, someone should totally tell him that," Raph agreed with a petty wave, indicating that even though it was his idea, he didn't care enough to act upon it. Leo made a little sigh at Raph's lack of interest, but shrugged it off and went to the lab.

As expected, the purple clad turtle was occupied with various kinds of projects. The whole lab seemed to be unusually crowded with stuff, and Leo got a strong feeling that Donnie must have made a trip to the junkyard very recently. He had no idea when Donnie had the time to do it, or even what he needed all the stuff for. Most of the things looked completely unrelated to each other. He could only imagine why Donnie would need an ironing board, where most of the padding seemed to have been chewed off. They didn't even own an iron. Or clothes, for that matter.

Leo tried his best to not trip over any wires or objects as he made his way through the mined area. The scientist was fiddling with a gadget that could barely be distinguished from all the tech bits and different colored cords that was attached to it. Donnie's tongue was sticking out in concentration while he tried to reach something through the cable-convention with a screwdriver.

"Hey Donnie," Leo announced, when he was close enough for a proper greeting. "Sorry to bother you, but... Have you seen Mikey?"

"Not since practice," Donnie answered without looking up, and picked up another screwdriver to assist the first one. "Why? What did he do this time?"

"Actually, he hasn't done anything," Leo said, and sounded surprised over his own statement. "Except for apparently finding a new home for a couple of triple-A batteries…"

"Uh huh," Donnie answered vaguely, his eyes fixed on the contraption before him. "I'm not sure if I'm following you here… Did you want to ask him something?"

"No, I just want to know where he is," Leo said with a shrug. "The thing with Mikey is that whenever he's doing something on his own, it's rarely something good. Especially for us. It tends to be related to new recipes, or water balloons with our names on them... Either way, I'd prefer to have a heads up so that I can take cover."

He gave Donnie a crooked smile, but his brother didn't pay him any attention. Leo observed him for a moment, before walking up to desk.

"So," Leo started a bit uncertainly, with a wary look at a jar of boiling ooze on the desk right next to Donnie. "are you getting any closer to finding a retro-mutagen?"

"Does it look that way from how I barely can contain my excitement?" Donnie replied bitterly, unscrewing something from the device's insides.

"Sounds like someone didn't sleep well last night," Leo pointed out, and folded his arms with a narrow look.

"Actually, I didn't sleep at all," Donnie corrected him.

Leo chuckled at Donnie's answer, as if it was meant as a joke, but went quiet when he noticed the drained look in the other turtle's eyes.

"Wait, you're serious?" Leo asked, in disbelief. "Donnie, that can't possibly be good for you, and you know it. You can't keep this up-"

"I'm not tired," Donnie told him casually, as he studied the device in his hand, almost as if he was trying to recall what he needed it for now again.

"Right," Leo said, with a doubtful look. "Well, at least this would explain why you've been so... gloomy all day."

"Gloomy?" Donnie asked, in surprise, and turned to Leo with a raised eyebrow. "I'm not gloomy. What makes you think I'm gloomy?"

"Except from the fact that you've kept to yourself all day and barely talked to us?" Leo asked, and leaned on the desk. "And that you let Mikey completely own you in the dojo earlier. I'm telling you. That was painful to even _watch_. You didn't exactly make it hard for him. Or any of us for that matter…"

Donnie looked as if he wanted to protest again, but hesitated with an uncertain look. His expression suddenly changed into a dejected one and he let his head fall back with a tired groan. He gave the screwdriver a look before he let it drop to the desk. Leo watched his brother with a concerned look.

"Is there anything you wanna talk about…?" Leo asked, and folded his arms. "I don't mean to sound bossy, but you seriously need a break."

"Okay, so maybe my mind has been a little… Occupied lately," he apologized, and put the wire-device aside as if he was done tinkering with it for the day. "It's just... I really thought I was getting closer last night. It's like I got all the pieces right here in front of me, but I can't see what the puzzle is supposed to look like. It's very frustrating, and I still have no idea how to solve it."

"I see," Leo nodded, with a sympathetic glance at the struggling scientist. "Look, don't be so hard on yourself. Nobody's is asking you to come up with a cure overnight."

"… But within a year would nice," Donnie mumbled to himself.

"Donnie, listen," Leo said, and put a hand on his brother's shoulder. "Beating yourself up isn't gonna help anyone. Just take the time you need, get some proper sleep, and you'll eventually figure it out."

"Eventually isn't fast enough." Donnie shook his head, with a depressed look.

Leo observed Donnie for a moment, but wasn't sure what to say to cheer him up.

"...I wish there was something I could do to help," Leo said sincerely.

"There is."

Leo turned to Donnie in surprise, not expecting his brother to take him up on his offer right away. Donnie watched him with interest for a couple of seconds before pointing to a small, handle-shaped gadget on a nearby table. The shape indicated that it once might have originated from the handle bar of a bicycle, and a car battery.

"Could you grab that for me?"

"… Sure." Leo agreed, and couldn't quite figure out why he hesitated.

He walked over to the table and picked up the object in question.

Pain.

Leo gasped as the electrical current ran through his fingers and down to his feet, frying every muscle on the way. The numbing feeling spread like a wildfire through every inch of his body, disabling every limb. Leo could feel his legs buckle against his will, and how his body fell to the floor. He landed heavily on his stomach. His brain felt so paralyzed that he wasn't sure whether it had hurt or not.

He could feel his consciousness drifting. Leo desperately tried to move his arms, but he could barely feel them anymore. His vision was getting blurred. Leo managed to raise his head somewhat, and his eyes fell on Donnie's feet. He had his bō by his side, and were standing right next to him. Leo opened his mouth to say something when he felt a something hard strike him over the head. The sharp pain was the last thing he felt.

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><p>"Leo? Can you hear me?"<p>

The voice felt unnaturally distant. Leo couldn't tell if it belonged to a forgotten dream or reality. His head hurt pretty badly though, so maybe that had something to do with it…

"… Donnie?" Leo mumbled in a dazed manner, not entirely convinced that it was his brother's voice he'd heard. It felt like all his senses were just getting back online after a major reboot. His brain tried to recover the lost memories, while his eyes struggled with the art of distinguishing shapes.

"It's okay. I'm right here, buddy," Donnie said reassuringly. "Everything is alright."

"No, I'm… I'm not…" Leo began hazily, as he slowly started to recognize the familiar surroundings of the lab. Something wasn't right. How did he hurt his head now again…? "… Wait, w-what did you-"

Leo's mind suddenly became wide awake when he realized that he couldn't move his arm. He turned his head to see what the problem was, only to discover that he was strapped down to a table. His arms, legs, and even chest were restrained with what seemed to be old, mismatched seat-belts. He stared at his tied down body in utter disbelief, and looked around for a context to the situation. His eyes landed on Donnie, who was standing right next to Leo's head. The purple clad turtle was quietly observing Leo, his curious eyes a little too close than Leo found comfortable. He noticed that Donnie was wearing his goggles on his forehead, along with a white lab-coat Leo didn't even knew that the turtle owned.

"… Donnie," Leo began calmly, while his arms violently yanked at the restraints. "What is this...?"

"Easy, easy," Donnie instructed soothingly and made a nonthreatening gesture, like when you try to calm down an agitated animal. "There's no need to freak out. You have just been secured to a table, okay? Everything is perfectly fine."

"That's _not_ the definition of fine," Leo explained, with a strained voice as he desperately tugged at the belts, but the tight straps prevented him from even twitching. "That's everything _but_ fine. What the heck is going on?"

"Well..." Donnie pondered, and curiously looked at the mess of experiments and junkyard trash around them. "A lot of things, to be perfectly honest. You're gonna have to be way more specific if you-"

"Why am I tied up!?" Leo interrupted, with a frustrated glare.

"Oh. Right," Donnie said, as if he hadn't been aware of Leo's predicament until just now. "Okay, the short version is that I think I've finally made some progress in my mutagen research."

"And the long version?" Leo asked, and tried his best not to yell the question.

Donnie didn't reply immediately. Leo felt how a hand brushed by his head as the turtle walked around him to get to his working desk. He leaned towards it in a contemplative way, before looking up with a fascinated look.

"Have you ever considered how absolutely incredible we are?"

"... I think Raph spends an hour a day doing it," Leo answered truthfully.

"The one thing we know for sure about mutagen is that it's _extremely_ unpredictable," Donnie continued, and started fiddling with some test tubes containing a red substance. "Whether it's humans, animals, or plants, it's nearly impossible to predict what the mutation process is gonna do to the subject once it's been exposed. That inconsistency is the main reason why it's so difficult to come up with a way of reversing the effects. Every case is so unique that it's hard to calculate how mutagen really works."

"... And?" Leo asked, with an uninterested look.

"_And_, that made me realize something," Donnie explained, with a victorious expression, not unlike that of someone who had just figured out how to cheat in a game. "I happen to be in the rare position of having, not one, but _three_ mutants with the _exact_ same kind of mutation as a result from mutagen exposure. If I conduct a more thorough study on your physiology, I could unlock the secret on how mutagen affects different individuals and species!"

Donnie smiled as if he had finished a successful presentation and expected applauds. But Leo just blinked at his brother with big eyes, similar to someone who was slowly realizing that he's swimming in shark water.

"You're kidding, right?" Leo said, with a wary look at the other turtle, hoping that he had misunderstood. "Donnie, you're _not_ experimenting on us."

"Actually, I a_m_ experimenting," Donnie corrected, and showed Leo the swirling content in the test tube he was holding. "I took this sample from you to study how your DNA reacts with my attempted retro-mutagen. I discovered that using mutated blood is by far the best way to determine if the retro-mutagen is working the way it should. I can't believe that I've never even considered doing this before..."

Leo's pupils were as small as pins as he observed this strange version of his brother, and the way he with great interest studied Leo's blood in his hand. The straps around Leo's chest felt somehow tighter than before. He really wanted this to be a prank. A hilarious practical joke by a guy who usually made puns about chemical symbols. But somewhere in Leo's mind, he knew that this had gone way too far for that.

"Donnie," he began, with a hollow voice. "Something... is very, very wrong with you."

"No, I'm fine," Donnie assured him simply, as if Leo just had asked him about his day. "But your sample looks a bit iffy... It doesn't seem to respond to my concoction at all."

"This is insane!" Leo exclaimed upset, and stretched the belts to their limits. He didn't care that it hurt. "Donnie, take these things off me and let me _go_! I'm not gonna help you with this!"

Donnie looked up from the vial of blood and observed Leo with a thoughtful expression, as if he was trying to figure out why his brother was so upset. He put down the sample and walked over to Leo's table. The older turtle turned away uncomfortably when Donnie leaned closer to his face and studied him with a curious look. Leo felt a nervous tug in his stomach. Was Donnie trying to diagnose him…?

"… I think I understand the problem," Donnie finally concluded with a serious look, and jumped over to a cardboard box on the floor next to the working desk. "But don't worry! I know exactly what you need…"

Leo didn't want to know what Donnie thought he needed. Donnie had already strapped him down to a table and, apparently, drawn a significant amount of blood from him while he was still out cold. Leo had no interest in finding out what Donnie had in store, but he knew one thing: It wasn't going to be pleasant. Not for him.

"Found it!"

Leo closed his eyes tightly. He couldn't move his arms. He couldn't move his legs. He was completely immobilized. But whatever Donnie was planning to do to him, he could at least choose not to watch.

"Okay… That's not very helpful," Donnie stated, unimpressed. "Open your eyes now, Leo."

Leo refused.

"Come on, what do you think I'm gonna do to you?" Donnie said, with a disapproving voice. "Don't be ridiculous, open your eyes. I think you're gonna like this."

Leo highly doubted that.

"Ah, I see…" Donnie suddenly said in a softer voice, and Leo flinched when he felt a comforting pat on his chest. "There's nothing to be afraid of. I'm just gonna give you something that will make you feel better. It's not something bad, I promise."

Leo shut his eyes even tighter, just in case his crazy brother would try to pry them open. After a minute, a sudden faint scent reached his nose, making the blue clad turtle raise an eyebrow in surprise. It smelled… sweet?

He finally opened his eyes, only to find a red lollipop one inch away from his face. Leo stared at the candy as if it just had started singing "Happy birthday to you", and then stared at Donnie. The scientist was still standing next to him, offering him the candy with one hand, while holding a whole jar of the stuff in his other. He looked at Leo expectantly.

"Lollipop?" Donnie offered.

"What…?" Leo asked, in disbelief.

"Here," Donnie insisted, and poked Leo lightly with it. "Have one."

"Where the heck did you even get those?" Leo wanted to know, and looked back and forth between the lollipop and Donnie.

"Same place I got most of this stuff," Donnie answered, and looked from the various bottles on the desk to his new lab coat.

"… When did you have the time to rob a hospital?" Leo asked, with a wary look at his brother.

"I haven't 'robbed' any hospital, thank you very much…" Donnie said with an offended look, and put the lollipop in his pocket. "These things belong to a private clinic a couple of blocks from here. Or, I suppose '_did_ belong' is a more accurate conjugation since they… Well… Don't have them anymore."

Donnie made a small awkward laugh at his own remark, as if the thought hadn't occurred to him until just now.

"Great. So you've only robbed a private clinic then," Leo stated sarcastically.

"I had to. I doubt that they would just give me the stuff," Donnie simply explained, and went over to the desk where he put down the jar of sweets and picked up a bottle instead. He studied the label with an intrigued look. "… and some of these things are kinda expensive."

"What else did you take?" Leo asked, with a serious look.

"A little of this, and a little of that…" Donnie answered vaguely, without looking up from the bottle. "… and then some."

"And none of this sounds wrong to you?" Leo asked in surprise.

Donnie moved his focus from the flask in his hand to Leo instead. He watched him silently with a puzzled look, as if he thought that Leo's question was very odd and wanted him to elaborate. Leo rolled his eyes in annoyance before looking up at his brother again.

"Donnie, this has to stop," Leo said, with authority. "You're not acting like yourself. You must have noticed that."

"Well, now when you're mentioning it…" Donnie admitted, with a thoughtful expression, which quickly changed into a confused one. "… Actually, no. I'm not sure what you're getting at."

"You tied me to a table!" Leo pointed out, and tugged at the straps to prove his point.

"Leo. It's for your own good," Donnie explained calmly, and put down the bottle. "We have a lot of procedures ahead of us, and many of them require the specimen to remain very still-"

"Specimen? We're you're brothers!" Leo protested. "I'm not sure what has happened to you, but it has to be something pretty bad if you're seriously considering doing this to your own-"

Leo didn't finish the sentence. He stared at Donnie in sudden realization, with an unnerving feeling crawling inside of him.

"… What have you done to Mikey?" he asked. The table felt strangely cold on his skin.

"Let me get back to you on that," Donnie replied as he put aside a couple of test tubes, and picked up a large syringe instead. "I need some more samples first so that I can finish the test properly."

"What?" Leo asked with a confused look, which was immediately replaced by a terrified one as Donnie approached him with the medical tool. "Whoa, whoa, hold on a second here! No, no. Stop it, hey- OW!"

Donnie didn't even hesitate before he plunged the sharp instrument into Leo's arm and penetrated the skin. Leo cringed in pain and watched the glass barrel fill up with red as Donnie slowly pulled the plunger. The view made him feel nauseous, and caused him to involuntarily look away as his brother retracted the needle from his flesh.

"There! Perfect," Donnie announced as he held the instrument up in the light, but then scratched his chin uncertainly. "...In retrospect, I should probably have gone with the 100 milliliter instead. I'm gonna need way more than this if I wanna do a sufficient amount of tests today. Why don't we have any vacutainers...?"

"Splinter is gonna find out about this," Leo pointed out, with a narrow look at the tiny puncture wound on his arm, wishing that he could rub off the stinging sensation. "You know that, right?"

"I'm not sure he will," Donnie commented absently, as he went back to his desk while swirling the sample above his head. "He drank a lot of tea..."

"What's that supposed to mean?" Leo asked, with a raised eyebrow.

"That I'm glad I was the only one who volunteered to make breakfast," Donnie explained casually, as he added the blood sample to a vial with a clear liquid.

Leo felt a shiver run down his spine, as he realized that there might have been another reason to why their sensei had decided to end their training sessions prematurely. Leo could suddenly feel how his worry was slowly being replaced by something else. It felt like fear. Fear of what was going on with his brother, and fear of what he could do to their family in his current state. But what concerned Leo the most wasn't Donnie's actions alone, but the fact that he was still talking and behaving just like the real Donnie. As if everything was just normal.

What could have corrupted his mind so terribly that he didn't realize that this was wrong?

"Alright, that should do it," Donnie said in a low voice, as he put away the vial in an old mini-fridge, which was covered with partly removed stickers. "Now I just need to add the new data to my journal, and then I can check on the first batch to see if it's unchanged."

"Look, Donnie," Leo started, with an uneasy expression, not sure how he was supposed to reach out to him. "I get that you're under a lot of pressure. Especially after April's dad got mutated into… a sort of red bearded, bug eating, mutant bat. But the point is that you have to give yourself a break. I know how hard it must be for you to create a retro-mutagen, I do, but-"

"Sorry to interrupt, Leonardo," he stopped him, and turned to Leo. His face was suddenly very serious. "but I'm gonna go ahead and correct you right there. You have NO idea how hard it is for me to find a retro-mutagen. In fact, you have actually no comprehension whatsoever of the level of difficulty I am experiencing in my attempts to find ways to fight off this whole alien invasion."

"You make it sound like you're fighting against the Kraang all by yourself," Leo pointed out with a disapproving glare.

"Am I not?" Donnie asked, and tilted his head slightly in a wondering way. "I am the one who make all the gear we use, the one who's monitoring the Kraang's communication device, decrypting their codes, and trying to find a way to reverse the effects from their mutagen. How exactly are you guys contributing to that?"

"You _know_ we are," Leo argued in frustration.

"And I can tell you how," Donnie added, and picked up a tray with surgical instruments from the desk and walked up to Leo. "You help me."

"... What are you doing?" Leo asked with a suspicious look at the tray, but he couldn't quite distinguish its contents from his awkward position.

"I need more information about how mutagen enhances natural abilities," Donnie informed him as he picked up an electric hand saw from the tray of equipment.

"What the heck is that thing?!" Leo exclaimed, and tried to lean as far away as he could from the machine.

"Something I wish was a rotary reciprocating saw..." Donnie admitted, with a critical look at the power tool, but then shrugged. "Let's call it that for now."

"Wait, wait, wait! W-what are you gonna do to me?" Leo panicked, as Donnie moved the saw closer to his body

"I'm testing the density of your shell structure," Donnie explained, as he gently stroked a spot on Leo's chest and then aimed the saw at it. "Just lie still, it'll be over in a few seconds."

"This isn't funny, Donnie!" Leo yelled and, despite the doctor's orders, desperately struggled against his restraints to get away. "Knock it off! I'm not gonna let you cut through my shell!"

"_Rel__ax_," Donnie said reassuringly, and looked at Leo as if his brother was being very unreasonable. "The carapace and plastron only picks up pressure differences, they hardly contain any pain receptors at all."

"HARDLY!?"

"Pun not intended. Ok, here we go," he informed, as he put on his goggles and turned on the tool with a roaring sound. "Try not to scream."

* * *

><p><strong>Next time:<strong> Leo's in a bit of a pickle, but how far is Donnie really prepared to go? Also, we'll find out where Mikey has been during all this…

**Author's Note:** Okay, I need your help, guys. I WANT to keep writing on this story (especially on chapter 3…!), but the problem is that I'm also working on the new chapters of "That time of year again". I meant to finish that story first, but then this little fella' just showed up in the middle of everything…! In other words: I don't know which story to focus on right now.

So I really need to know what you guys think. Should I keep writing on this one? Would you like to read more?


	3. Chapter 2: Larger Needle

**Author's Note**: Thank you for sticking around! It means a lot to me, and just reading reviews that simply say "love this" or "please keep writing" is an incredible boost for me! And not to mention the ones who teach me phrases such as "Holy shmacknuckles". XD It completely made my day, and I thank you for it. ^-^

I'm just so happy that there are people out there who like this story, because it has really given me the motivation to keep going. :) And I SO want to keep writing on this puppy now…! I can tell you that things will escalate quite nicely from here on, and there's some stuff I can't wait to start working on. :D

I really hope you'll at least stay for chapter 3! It's gonna be a juicy one. ;)

* * *

><p><strong>Chapter 2: "Larger needle"<strong>

Leo squirmed in panic and did everything he could to escape. But the seat-belts would barely let him move anything but his head. The sharp blade of the power tool was rotating in extreme speed as Donnie carefully lowered it towards Leo's vulnerable front. The machine was emitting a strong, stinging smell of burnt plastic, giving Leo the impression that this device also originated from the junkyard. Leo watched in horror as it wasn't even an inch away from him. He was well aware of the protective ability of his breastplate, but he had no idea how it would feel like to have it cut open by an electric saw. And frankly, he did not share his brother's enthusiasm to find out.

"Donnie! DONNIE!" Leo yelled, in order to be heard over the machine. "You _can't_ do this! Please, this is so, SO wrong… You have to realize that. Donnie? _Donnie, you have to STOP!_"

To his surprise, Donnie suddenly turned off the tool, and moved his goggles back to his forehead with a wondering look at his brother.

"Would you like to be sedated during this procedure?" he asked, and tilted his head curiously.

"I don't want you to do it at all!" Leo exclaimed in anger, and stared at the sharp tool in horror. Dreading the moment it would roar to life again.

"Good, because I'm afraid I spent most sedatives on Master Splinter," Donnie said, apparently interpreting Leo's answer as a 'no'. "You'd be surprised how tricky it is to figure out the right dosage for a mutated man-rat... Unless you want to kill it, of course."

He made a nervous laugh at the last add and scratched his neck, as if he had made a mildly successful joke. The scientist stopped almost immediately as he seemed to remember something. He put away the hand-saw and went over to his desk, where he loudly rummaged through a drawer. Leo raised an eyebrow when Donnie came back with a black marker in his hand.

"Also," he added encouragingly, and rested a hand on Leo's chest as he, with great concentration, started to mark out certain spots on his plastron. "by _not_ sedating you, I can find out exactly how much strain the shell can endure before the body starts experiencing discomfort."

"... Are you saying that you want to see me in _pain_?" Leo asked, and stared at the tall turtle with an unreadable look.

"Not really," Donnie answered, and barely looked up at the question. "It's not exactly something I'd enjoy watching. I prefer to think of it as an inevitable consequence of a necessary procedure."

Leo had no idea how to respond to this. The whole situation felt surreal to him. And the fact that his brother was currently drawing on his chest didn't exactly help. Leo had barely noticed that his breathing had quickened, but Donnie apparently had. He swiftly glanced at Leo with a raised eyebrow.

"Why do you look so nervous? Are you worried about the test?" Donnie asked, in surprise. "Don't be. According to my estimation, this shouldn't be worse than anything you haven't felt before. I'm sure you can handle it. You're threshold of pain is rather impressive."

Donnie smiled at him as if he had just given Leo a compliment. Leo answered by tugging at the belts again. Maybe he had managed to loosen them up a little? Or maybe he could break free from them if he really put his mind into it… Donnie had probably found them at the junkyard along with the rest of the stuff, so how strong could they be?

Donnie watched his brother struggle with the straps for a moment with a concerned look. He then put down the marker and reached for something in his pocket. Leo immediately tensed up and stopped his attempts. He watched Donnie with a wary look, but then blinked in surprise when Donnie picked up the lollipop again. The scientist studied the candy for a second, and then smiled as he offered it to Leo.

"No thank you," Leo said deadpan.

"It'll make you feel better," Donnie encouraged.

"No it won't," Leo told him firmly. "The only thing that would make me feel better right now is if you loosened these straps."

"Are you sure…?" Donnie asked, in a tantalizing way, ignoring Leo's request. "It's strawberry."

"Pass," Leo answered.

"Or maybe you'd prefer lemon-"

Donnie trailed off as Leo gave him an irritated glare, making the other turtle sigh and turn away. But the scientist seemed to quickly shake off the rejection as he happily put the lollipop in his own mouth instead. He frowned slightly at the taste.

"Huh. I was wrong," Donnie stated, and took out the candy to look at it. "It kinda tastes like cherry."

Donnie observed the sweet for a few seconds. He then made a light shrug and put the lollipop back in his mouth with a pleased look. Leo watched his brother uncertainly as he picked up the marker again and went back to drawing on Leo's torso.

"What exactly are you doing over there?" Leo asked with an awkward look, stretching his neck in an attempt to see what Donnie was up to. "In case you haven't noticed, I'm not a whiteboard."

"It wouldn't make much sense if you were, since this is a permanent marker," Donnie pointed out, as he circled something on Leo's left side. "I'm just outlining where it should be safe to do the incisions. In case I go too deep and damage your internal organs. I actually should have done this from the start, especially considering that this power tool is _way_ inadequate for anything involving precision."

He gave Leo a reassuring look as he made a straight line right over his midsection as a finishing touch, and picked up the saw again. He then hesitated and sniffed the air suspiciously. Donnie followed the smell to the tool and gave it an unfavorable look. Apparently, he wasn't a fan of the burnt plastic smell the appliance so generously shared with its surroundings. Donnie went over to his desk again, and soon returned with a white surgical mask. There was a crunching sound as he bit off the candy in his mouth and tossed the stick aside before putting the mask over his face.

"Alrighty then," he declared, and started the machine again. "Let's get this over with, shall we?"

His eyes were smiling when he covered them with the goggles. The dark, protective glass hid them completely, only leaving a pair of black voids instead of eyes. Together with the mask, the goggles stripped his face of all emotions, only leaving a nameless being with an electrical saw and every intention to use it. The air escaped Leo's lungs when the noisy device once again was aimed at his body.

"Wait, stop. STOP! Donnie, listen to me!" Leo insisted. His heart was pounding so hard in his chest that it felt like it was trying to beat him up on the inside. "You don't wanna do this. You _can't_ do this! Do you understand? Don, can you hear me? For crying out loud, this is wrong! Can't you see- No, no, stop! Please, Donnie, don't- ah- AAAH!"

Leo made a sharp inhale when he felt the toothed edge make contact with his armored front. He closed his eyes tightly with an agonizing expression, unable to watch what was happening. He could almost feel how tiny fragments of his shell hit his face from the brute, invading force. He felt ill to his stomach. A part of him wished that he could just abandon his body, and come back another day when this whole nightmare was over. It had to be a nightmare. This couldn't be happening to him for real. There was no way that his own brother was standing above him right now, trying to saw through his shell just to satisfy some messed up scientific curiosity. Not Donatello. Never him.

Leo wished that the illusion could have stayed with him a little longer. He screamed when he felt a sudden searing pain hit his upper right body.

"I said: HELLOOOO! Donnie? Can you hear me? I've been calling for, like, five times!"

"Eleven, actually..." Donnie mumbled miserably, like someone who had given up on ever feeling happy ever again.

Leo barely reacted to the loud, familiar voice at first. He didn't even become aware of his surroundings until he felt how the torturing pressure on his chest was lifted, and how the deafening sound of the machine stopped for a second time.

"Oh," Mikey answered in surprise. "So... You _can_ hear me?"

"_Yes_, I can...!" Donnie replied tiredly, and rubbed his left ear with a grimace as he moved his goggles and mask aside. "Look, if I don't answer when it's obvious that I should have heard you, it's safe to assume that I simply don't have the time to talk, okay? There's no need to bust someone's ear-drums just to make sure that they haven't gone deaf. In fact, such an action _would_ most certainly impair someone's hearing for real."

Leo was still panting heavily from Donnie's 'test' when he finally recognized Mikey's voice. He quickly turned his head to the direction of the sound, as to make sure that it really was his little brother that he had heard. He wasn't disappointed. Michelangelo was standing at the entrance of the lab, and was currently flipping the TV-remote between his hands like some sort of toy.

"Heh, sorry bro," Mikey said, and gave Donnie an apologetic smile, but then happily strolled inside with the device. "But could you take a look at the remote? I don't know what's wrong with it. It doesn't wanna change channel, or sound, or… Okay, it doesn't do anything remotey at all. I think someone busted it. And I _swear_ it wasn't m-"

Mikey suddenly stopped halfway through the area, and looked up at the scene in front of him. He seemed to just now have noticed the lab-coat Donnie was wearing. Along with the mask around his neck, the goggles on his head, and the electric hand-saw in his grasp. Mikey's eyes then fell upon Leo, who was lying on a table next to Donnie's desk in a firmly secured position. Leo looked at Mikey with eyes that were screaming.

All three turtles just stood there and blinked at each other for several seconds, not saying a word. The situation almost looked comical.

"You guys never tell me stuff!" Mikey suddenly exclaimed, with an upset look at his brothers, as if he'd been left out from a secret club-meeting. "Fine! Maybe _I'll_ go off and do something that _you_ don't know about. By myself! Then you'll see how fun-"

"Mikey, listen!" Leo called out hurriedly in short breaths. "Go find Raph. Get him here _right now_! Donnie's gone nuts!"

"I haven't gone _nuts'_," Donnie claimed with a bored voice, and rolled his eyes. "I'm merely taking my research to the next level in order to speed up the progress of creating a retro-mutagen. You even offered to help me, remember?"

"I didn't ask to be cut in half with a saw!"

"Stop overreacting, I would never do that," Donnie claimed with a dismissive wave, but then looked thoughtful. "However, if I wanted to dissect you, a simple Y-incision through the chest would be a much more professional approach."

"… You guys are totally messing with me, aren't ya'?" Mikey asked, and looked between his two brothers with a suspicious look.

"Mikey, _please_!" Leo yelled insistently, with piercing eyes. "Just run! NOW!"

Mikey still looked thoroughly confused over the bizarre situation. But there was something about the urgency in Leo's voice and the desperation in his eyes that made Mikey realize that whatever was going on, it wasn't right. He slowly took two big steps backwards, away from the scene. Then one more, for good measure. In the next second, he turned around and made a dash for the exit, like a rabbit for a burrow.

Donnie sighed at this, and reached for his staff that was leaning towards the desk. He skillfully spun it in his hand, while watching Mikey's movements closely. He then let go of his weapon and watched it soar through the air. It hit his younger brother right behind his knees. The freckled turtle yelped in surprise as he ungracefully tumbled around on the ground and ended up on his stomach.

"I keep telling you: don't run around in my lab," Donnie explained, with an annoyed gesture, as he walked over to his brother. "You could break something."

"… Like me?" Mikey suggested, with an uncertain smile at him.

"For example," Donnie nodded, and offered him a hand to help him up.

Mikey looked back and forth between Donnie and the outstretched hand with a puzzled expression. Obviously uncertain of why the hand that just had assaulted him suddenly wanted to assist him. After some hesitation, he took it and let Donnie pull him back up on his feet. The orange clad turtle gave Leo a lost expression, as if he deeply wished that someone could explain the situation to him.

"Do you still have the TV-remote?" Donnie asked Mikey, as he picked up his staff from the floor.

"Um... Sorta?" Mikey answered hesitantly, and held up the gadget. He had to use both his hands, since it was the only way to keep the crushed pieces somewhat connected. "I think it kinda ended up underneath me?"

"Well," Donnie pondered, as he curiously poked at the remains. "judging by its current state of structure, I'd say that's a fair assumption."

"Sooo..." Mikey stretched out the words in a stalling way, and subtly tried to make eye-contact with Leo. "Maybe I'll go away while you, like… you know… Fix it or something?"

"_If_ I can fix it," Donnie answered, with a skeptic look at the pieces. He leaned his staff towards the wall as he went through one of his pockets. "Just give me a sec."

His hand came back holding a cable-tie. Before Mikey had time to react, the older turtle had wrapped it around his brother's outstretched hands, locking them tightly together.

"... Hey, uncool- OOF!"

Donnie had swiftly taken his bō and hit Mikey hard in the stomach with it, knocking the air out of the younger turtle. Before Mikey could catch his breath, his brother used the weapon to push him in the opposite direction. Mikey stumbled backwards until he hit a revolving chair a few steps behind him and fell down in it, making the chair roll away several feet and slam into the nearest wall. Mikey looked up dizzily from the unexpected impact, and barely noticed that Donnie was already by his side, securing his body to the chair with a white power cord.

"Okay… I think that should do it," Donnie decided, when he had finished the last knot on Mikey's upper body and then used another cable-tie to force his feet together. "Sorry about the improvised placement, I didn't really expect to have another specimen so soon. I'm not even sure what to do with you yet..."

"Maybe let him go?" Leo proposed sincerely.

"No, I think we better keep him here," Donnie concluded after some thinking, and moved Mikey like a wheel-chair to a more comfortable distance from the working desk. "Like you said earlier, it's kinda unnerving when he's on his own. This way, we can both keep an eye on him. And you don't have to worry about getting ambushed by water balloons."

Donnie reached his destination, but suddenly frowned and observed Mikey for a second. He then turned around to Leo with an annoyed stare.

"He's totally gonna try to wheel away in this thing, isn't he?" he asked, and pointed at the subject with his thumb.

"What? Nooo…" Leo assured him, with a nervous laugh. "I can't imagine that."

Donnie watched Leo for a moment, but then turned his eyes back to the revolving chair. Mikey had already made it move several inches away from Donnie's side by pushing it away with his toes. When he realized that his attempts had been discovered, he made an apologetic laugh and pulled his knees up innocently.

"... Keep your feet up," Donnie instructed, and grabbed his staff again. He walked up to the turtle, ejected the naginata blade, and then slashed it four times at the chair's lower regions. Mikey made a startled squeak as Donnie chopped off the chair's only means of transport. The wheels rolled away in swirly patterns all over the floor, leaving the younger turtle completely stranded. Mikey tried to catch a glimpse of the destruction underneath him, but got distracted when Donnie crouched beside him and used the gas-lift to elevate his seat.

"Oh, come on!" Mikey complained, as he realized that he couldn't reach the floor anymore. "Not cool, dude! _Not_ cool! Why is this chair so high anyway? Who needs a chair this high?!"

"I got longer legs than you." Donnie shrugged, and glanced at a nearby watch. "I need to check on my samples now. It could take a little while, so I would greatly appreciate it if you two could keep it down a bit? I haven't slept very well, so I really need all the concentration I can get..."

Donnie left his brother's side and walked over to his working desk. He quickly retrieved a vial of blood from the min-fridge and applied the content on a glass slide.

"... Bro," Mikey said, in a very loud whisper to Leo. "I think Donnie is a few pepperonis short of a good pizza, if you know what I mean."

"That's a bold statement coming from someone who's about as sharp as an ellipse," Donnie muttered, and looked up from his work with a narrow look. "And for your information; that was for all intents and purposes _not_ a whisper. I can barely hear myself think over here."

"... Is he sick or something?" Mikey carefully asked Leo in a lower voice, as he watched how Donnie went back to work.

"What kind of disease would make him act like this?" Leo asked, with a careful glance at the preoccupied scientist. "It's so weird, I mean... He's still Donnie, but it's almost as if he doesn't get that he's doing something wrong. He doesn't understand… It's like someone pressed a button and turned off that part of the brain that's... supposed to warn you when you're about to do something crazy."

"I _swear_ I didn't push any buttons this time, honest!" Mikey claimed with an insistent look at Leo, but made a surprised frown when he noticed his brother's chest. "Dude, what did he do to you?"

Leo had to think twice before he understood what Mikey was referring to. He hadn't even looked at the spot on his plastron that Donnie had been working on. Leo quickly closed his eyes and turned away his head with a pained look.

"… is it bad?" He asked with an uneasy sigh, not sure if he wanted to know the answer.

"Your chest kinda looks like a treasure map," Mikey informed him straightforward, and studied the patterns from the black marker with interest. "With _a lot_ of treasures... Does that count as bad?"

Leo took a deep breath before he glanced at the area. He couldn't quite distinguish Donnie's drawings, which seemed to consist mostly of lines and letters, but he could see the cut from the saw. It didn't appear to go deep, but it was hard to tell for certain. He could still feel a throbbing pain emanating from it. He turned his head to catch a glimpse of the saw. The blade looked like it was covered with tiny spots of rust. Or blood. It was hard to see the difference from his angle.

"I guess it could be worse." Leo swallowed uncomfortably, and decided not to dwell on what would have happened if Mikey hadn't showed up when he did.

"I'm not so sure," Mikey said, and shook his head knowingly. "That stuff doesn't come off. You remember when we were kids and you guys drew on me? It took like _weeks_ before it disappeared. I even tried with soap. Didn't even smudge it a little."

"Wasn't it Raph who drew on you…?"

"Yeah, but you didn't stop him…" Mikey reminded him, with an accusing look.

"Okay, maybe. But right now, Raph is our best hope," Leo told him, in a low voice. "He has to realize that something is wrong soon. And when he does, I can't picture Donnie being able to stop him."

"And that will be the end of Dr Donnie-stein!" Mikey announced cheerfully. "No, wait, Dooms-Don! Or Professor Donato, or the Terror-Tello! Or Dr Dona-"

"Stop it!" Leo scolded. "You can't give him one of your monster-names, he's our brother!"

"… Donnie Darko!"

"Mikey, I will kick you...!"

"I don't think you can reach me," Mikey informed him with a superior smile, as he started to spin the chair, with the great skill of someone who has turned the act into an art form.

He was so caught up in the spinning that he didn't notice that his elevated feet accidentally hit a small nearby table with some lab equipment. Mikey stopped the moment he saw the wobbling table with the fragile looking glassware, and both he and Leo cringed when some empty bottles rolled off and loudly crashed to the floor. The noise made Donnie cry out in surprise, and the two turtles turned around just in time to see Donnie, with poor juggling skills, trying to save two vials from falling off the table. The blood filled containers slipped through his insufficient number of fingers, and soon joined their neighbors on the floor in a puddle of glass and liquid.

"Oh man..." Donnie moaned, with an unhappy look at the mess in his lab. "Nice going, Mikey! Look what you made me do."

"It wasn't my fault. You put me in a chair that goes like this!" he argued, and made the chair spin again to emphasize his point. "Who would put glass-stuff next to that?"

"He kinda has a point, you know," Leo felt the need to point out.

Donnie facepalmed and shook his head, apparently recognizing Leo's impeccable logic and wishing that he could have seen this coming. He turned back to the broken glass with a sigh.

"Terrific," he stated bitterly. "I can't continue unless I get new vials of samples. Guess it's only fair to make this Mikey's turn..."

He went back to his desk and picked up the same kind of syringe he had used on Leo earlier.

"What? No, you can't," Leo said sternly, and stared at the syringe. "Donnie, put that thing back. Put it back _now_! You're not doing this to Mikey!"

"What is it? What's he talking about?" Mikey wondered curiously, and tried to spin the chair to get a clearer view on what Donnie was fiddling with.

"It was an accident…!" Leo tried to argue. "Are you really gonna punish him for something he didn't even mean to do?"

"I'm not trying to punish him. I'm just allowing him to replace the samples he destroyed," Donnie explained with a reasonable voice as he studied the needle, but then he seemed to remember something. "Oh, right, I need the 100 milliliter."

He put the tool back and instead picked up a syringe that looked like it was the bigger, meaner cousin of the first one.

"Donnie, you can't hurt him!" Leo protested, with an angry look at the taller turtle. "You can't hurt your own little brother!"

"He's gonna hurt me with that thing?!" Mikey cried out in sudden realization. His eyes were fixed on the sharp tool in horror. "For real? With _t__hat_?!"

"Thanks a lot, Leo. Now you've scared him," Donnie scolded, with a reproachful look at the leader.

"I don't want him to take my blood! I like my blood, I wanna keep it!" Mikey yelled in panic, and shook his head so violently that the chair wobbled slightly.

"Don't be such a baby, you have approximately 1,2 gallons of the stuff. You're not even gonna miss it," Donnie informed him in annoyance, as he made his way to Mikey while studying the size of the needle. "You might feel a slight pinch though…"

"Wait! Let me do it," Leo suddenly exclaimed, his eyes watching Donnie intently. "Take my blood instead."

Donnie stopped in his track and turned towards Leo with a frown.

"Why?" he asked, with his hands out in a wondering gesture.

"Because..." Leo began hesitantly. He hadn't expected Donnie to ask for an elaboration. "Just… Look how much he's moving around. He's clearly upset. It's gonna take you forever to get a good sample from him when he's like that, right?"

"I could always just knock him out," Donnie mused.

"_Or_, "Leo hurriedly interrupted, not wanting Donnie to get too familiar with the idea. "you could use me instead. It makes sense. You've just lost your samples, and every minute wasted on getting new ones from Mikey is time you could spend on something more important. If you use me, I won't fight back. You can take as much as you want, and you'll get what you need way faster. And if you really need a sample from Mikey too, you could always do that later, right?"

"… I suppose the result would be less inconsistent if I used the same DNA as the first batches," Donnie said and scratched the back of his neck in a contemplative way. He then shrugged and walked up to Leo instead.

He positioned himself at Leo's left side with his back towards Mikey, looking for a good area to insert the needle.

"But I strongly recommend you to not tense up like you did the last time," Donnie warned, and poked Leo's arm until he found a favorable spot. "It will be less painful that way. And I don't think I need to tell you; this is a bigger needle."

"... I'll try." Leo nodded slightly, and closed his eyes.

"Sorry, bro..." Mikey said in a broken voice, watching in distress how his big brother's face winced when the thick needle entered his body.

* * *

><p><strong>Next Time<strong>: Leo won't let Donnie hurt Mikey, but how long can he keep this up? And things take a grim turn when it's revealed that Donnie has been conducting another experiment on the side.


	4. Chapter 3: 48,9 percent

**Author's Note**: Are you guys still with me? I hope so. I would miss you if you suddenly went away… (ó.ò) And please don't leave me alone with Donnie! D: He hides stuff in his pockets! BAD stuff!

I want to thank you all for the support, and for telling me that you like this fic! Every single review is HIGHLY appreciated and really makes a difference. It's so much more fun writing something, knowing that I'm not the only one who likes this story. And if you're here solely for the Apritello, I can tell you that it's not far away now. I'm personally really looking forward to when April and Casey shows up. Things ought to get interesting… Hope you'll stay for it!

As always, look out for them grammar-gnolls and odd-trolls in the text! I always read it through three times, but some errors just like to hide until I've posted the darn thing…

* * *

><p><strong>Chapter 3: "48.9 percent"<strong>

"...There. One more vial should do it," Donnie declared, as he carefully retracted the needle from his brother's increasingly abused arm. He studied the red liquid with interest.

"You said that the last time..." Leo protested weakly. His body ached and he found it difficult to keep his eyes open.

"Sorry, I thought I meant it the last time," Donnie explained, with an apologetic laugh, as he walked over to his desk and filled up some test-tubes with the syringe's content. "I keep underestimating the volume I need in order to make a sufficient number of tests. It would go faster if I had some better equipment to work with, but as I'm sure you can imagine, good quality medical tools tend to be a little bit sparse in a city junkyard."

He added the filled tubes to a long line of shining red vials on his desk. He gave his collection a pleased look before he went back to Leo with the now empty syringe. He felt along Leo's arm for a new place to apply the needle, when he suddenly caught a glimpse of his brother's weary face. Donnie gave him a kind smile and rubbed his shoulder in a reassuring way.

"Just relax, you're doing great." he soothed, raising the needle and gently placed it against his bruised skin again. "Just one more time, okay? You can do it, buddy."

The thin metal that entered him hurt just as much as the other times. But Leo could barely summon the energy to recognize the intrusions anymore. He felt tired and worn. He had lost count on how many tubes of blood Donnie had taken from him by now. He had avoided looking at the desk to find out the exact amount. He had tried to keep up a tough front in the beginning of the process. But it had become increasingly difficult, since the scientist repeatedly discovered that he needed more samples than he had initially thought. He always apologized. And he always came back for just a little more. Leo's tough front had slowly started decaying when he began to realize that there was no telling how long Donnie would keep doing this to him.

"Are you okay Leo...?" Mikey asked worriedly, and twisted his neck in all kinds of directions in order to see past Donnie's back. "You're okay, right? Right? ...Leo?"

Leo felt the brief feeling of relief when the needle left him, and was only somewhat aware of Donnie disappearing from his side. He felt woozy. Lightheaded. His eyes couldn't find anything to focus on. Was the table spinning...?

"_No_!" Mikey barked at him with a stubborn look, making Leo cringe from the sudden noise. "You can't pass out now, bro, you hear me? No way, uh-uh, forget it! You can't leave me alone with him! He's gonna do stuff to me, I just know it! Don't go anywhere, dude, you gotta stay with-"

"I'll be fine Mikey," Leo assured him, and even managed to give his brother a faint smile.

The freckled turtle went silent, but soon answered him with a happy grin. Apparently, it was all he needed to hear. Whether it was true or not.

Leo shook his head slightly to clear his thoughts. Mikey's voice had rewarded him with some motivation to stay in control. To not let his mind drift off like that again. He hoped the feeling would stay with him.

"We need to stall him," Leo informed Mikey in a low voice. He subtly glanced at Donnie, but the scientist seemed too busy with the latest addition of mutant blood to care about anything else. "Like… Keep him talking about something else, anything to distract him from his experiments."

"No problemo!" Mikey concurred, and somehow managed to make a thumbs up with his tied up hands. "Hey! Don! Um... What's the deal with the lab coat?"

"Because turtle shells don't come with pockets," Donnie answered absently, while filling up another vial with Leo-blood.

"…Oh. Cool," Mikey answered with a blank face, and fell silent for a moment. He then turned to Leo with a raised eyebrow. "Sorry, I'm all out."

"That's all you got?" Leo asked, with a doubtful look at the king of unasked questions.

"What am I supposed to do? He doesn't give me any material," Mikey argued with an upset gesture at the subject. "Shells don't _have_ pockets."

Leo made a sigh at Mikey's reasoning, but gathered some strength and turned to the scientist himself.

"So, Donnie... " he started calmly, trying to sound casual. "When did you feel like taking your research to the 'next level', as you put it?"

"I'm not entirely sure, to be perfectly honest," Donnie replied, after giving the question some thought. "But according to my notes, I had some sort of epiphany last night after some major setbacks in my research. I think that has something to do with it."

"What kind of epiphany?" Leo asked innocently, figuring that this information could be useful for them.

"Hard to say. I get a lot of epiphanies; I can't keep track of them all." Donnie shrugged lightly, as he put away yet another vial with red content. "My mind has been extremely active lately, it's nearly impossible to recall which chain of thoughts that spawned which idea first. It's like trying to trace back a dollar bill to whoever had it two weeks ago. You could always try, but it doesn't change what you're gonna buy with it."

"It does if that guy wants to give you another dollar," Mikey suggested, with a hopeful look.

"He doesn't," Donnie clarified with a narrow glance at his youngest brother. "Because people don't throw their money at man-sized, mutated turtles with weapons. Not unless they're being mugged by one."

"... But what if the turtle _saves_ the guy from getting mugged!" Mikey brightened up, as if he had just discovered the answer to life, universe, and everything. "No, wait! If the _guy_ mugs a turtle, and then another guy _saves_ the turtle and then-"

"Are you feeling well, Leo?" Donnie suddenly asked with a frown, turning his attention to the blue clad turtle instead.

"... Why do you ask?" Leo wondered hesitantly, trying to come up with an answer that wouldn't result in Donnie stabbing him with more needles.

"Because you're looking a bit pale," Donnie pointed out, and got up from his desk for a better view.

Leo was just about to give Donnie a dry comment on that particular fact, but didn't feel like wasting the energy, and firmly closed his eyes instead. He needed to keep his mind clear. To not give in to the constant presence of fatigue. When he opened his eyes again, he was surprised to find Donnie suddenly standing right next to him.

The tall turtle looked down on his brother with a hint of concern in his eyes, and reached out a hand towards him. Leo flinched involuntarily when his brother's hand came in contact with his skin, but then frowned when he felt Donnie rest his hand on his forehead. As if he was feeling his temperature.

"... Hm," Donnie said, as he looked up in a pondering manner.

"What?" Leo couldn't help but ask, with a distrustful look at the scientist.

Donnie didn't feel obliged to answer him. Instead, he went over to his desk again, picked up some sort of cuff with a lot of colorful wires attached to it, and came back to wrap it around Leo's un-abused arm.

"Do I wanna know what's this thing is?" Leo asked with a raised eyebrow, as Donnie made sure that the unit was firmly secured to him, and then followed the wires back to a plug which he connected to his laptop.

"I'm just hooking you up to my computer so that I can monitor your vitals," Donnie explained in a conversational manner, as his fingertips danced over the keyboard. "You know, like blood pressure, body temperature, pulse, and respiratory rate. Pretty cool, huh?"

Donnie proudly turned the screen towards his brothers. It was covered with blinking windows of counting numbers, changing colors, and squiggly lines. Donnie gave his brothers an expectant grin, but his shoulders slumped in disappointment when the other turtles unanimously shook their heads with unimpressed looks. The scientist made a small sigh as he turned back to the screen and immersed himself in decoding all the information he was receiving.

"Is there something wrong with Leo?" Mikey wondered, as he looked between his two brothers with a puzzled expression.

"His blood pressure's a little off," Donnie eventually informed, as he leaned back in his chair with his finger tapping his chin. "It's most likely the result from losing high levels of blood-plasma and body fluids. But it's a bit strange though. You shouldn't experience any hypovolemic symptoms yet. Then again, it could be related to the extensive training session we had today. I probably should have taken that into consideration... Do you experience any other discomforts?"

"I don't know," Leo shared reluctantly. "Maybe a bit-"

"Thirsty?" Donnie suggested, still with his finger to his chin in a contemplative way. "Dizzy and nauseous?"

"... Maybe," Leo admitted, with a defeated sigh.

"Yep. That's consistent with hypovolemia," Donnie stated after a moment of consideration, and left the computer to get back to his blood samples. "Man, I knew I should have brought some IV bags... Oh, but don't worry about it. The symptoms should go away on their own. You'll just have to take it easy until your body has replaced the missing fluids, okay?"

Leo made a tired groan, and watched Donnie apply some of the samples on petri-dishes containing some sort of orange substance. "Okay," the scientist began slowly, as he with great concentration used a pipette to get the right amount of blood on the dish. "Now I just need to incubate this batch to see if the retro-mutagen will make your DNA revert back to normal. To the DNA of a normal freshwater turtle, that is."

"What's up with that jar over there?" Mikey suddenly asked, and was referring to the jar of boiling mutagen on the far off area on the desk. His eyes had been watching it in the same manner a mosquito watches a lantern.

"Just a little project I'm doing on the side," Donnie told him, as he put away two of the dishes in an incubator.

"… Are you sure that green _smoke_ is part of the project too?" Leo asked, with a concerned frown at the clouds that were constantly ascending from the container. "It looks kinda... mildly super-toxic."

Donnie ignored his question, and was busy fiddling with the incubator's settings.

"Aaand, done!" he announced when he took a step back from the machine, and then gazed at his occupied desk. "Took me long enough, but now I think I'm finally back on track again."

"And since you've been so busy," Leo tried, with an inviting voice. "maybe you deserve some time off? You know? Rest up a little before you continue? We won't mind."

"Not yet," Donnie pointed out, and started looking through a drawer. "I still have to get some samples from Mikey."

"_What!?_" Mikey exclaimed in utter shock, and stared at Donnie as if his head just had exploded.

"You said you would leave him alone!" Leo protested agitatedly.

"I didn't say that." Donnie shook his head, as he resurfaced from the area with a new large needle. "I just agreed that it made more sense to take samples from you first. You know, for consistency."

"Then keep using me!" Leo argued, feeling how his beating heart was making him pant. "You don't need Mikey, just... Take what you need from me, okay?"

"I'm sorry Leo, but you're the only one who can't," Donnie tried to explain, as he stopped by his side on the way to the younger turtle. "You're already displaying classic signs of decreased blood-volume, and that road really only ends in one way, and that's hypovolemic shock."

"Do it anyway," Leo ordered. His breath was weak but his eyes determined. "I can handle it..."

"... You really think you can, don't you?" Donnie stated, with an almost apologetic look. "But it doesn't matter. I need Mikey's blood too so that I can compare it with yours. There's a slight risk that the retro-mutagen reacts differently on individuals. I need to know that for certain before I can proceed."

"No! I'm not doing it!" Mikey yelled at Donnie, his face contorted with uncontrollable panic. "I don't want that thing in me! Get it off of me, I can't do it, no, no, NO!"

Mikey was struggling against his bonds with such uninhibited distress that the chair was wobbling dangerously where it stood.

"What are you _doing_?" Donnie asked sharply, and turned to him with an annoyed look. His brother immediately ceased his efforts and watched Donnie uncertainly.

"… stopping you from sticking that thing in me?" Mikey answered hesitantly, and observed his unamused brother with a tilted head.

"So you figured it would hurt _less_ if I stick a needle in your arm while you're flailing around like that?" Donnie wondered with a narrow look, and held up the needle. "You do realize these things can break, right?"

Mikey blinked at him in confusion, not sure how he was supposed to proceed from this point. Donnie made a tired sigh, and walked up to his left side with the pointy tool. He immediately started to search Mikey's arm for an appropriate area to insert the needle. Mikey was trying to lean as far away from his brother as possible, his chest heaving rapidly accompanied with small high-pitched breaths.

"Stop hyperventilating, you're gonna faint," Donnie warned, having trouble concentrating because of the noise.

"Fine! Maybe I _wanna_ faint!" Mikey stated with a defiant glare at his brother, and deliberately accelerated his breathing to an alarming speed.

"It's _not_ fine. Cut that out," Donnie scolded, and effectively stopped Mikey's attempts by covering his mouth and nose with his hand. "You're depleting your body of carbon dioxide which could cause hypocapnia and make you sick. Also, if you pass out, you have no way of knowing how long you'll stay unconscious! It could be for minutes, hours or it could be for the rest of the day. Does this still sound like a good idea to you?"

Mikey stared at Donnie with wide eyes. The horrifying images of what Donnie could do to him if he stayed unconscious for a longer period was apparently enough to make him want to stay alert for now. Donnie removed his hand when he was certain that Mikey was trying to breathe normally, and turned his attention back to the arm.

"Good. It'll be over much quicker if you cooperate," Donnie told him, as he carefully aimed the needle at a spot. "Just try and sit still and breathe like a normal person. Trust me, you don't want me to slip with this thing…"

Mikey made a pitiful pained sound when Donnie forced the tool through his flesh and slowly started to pull the plunger to fill it up with his precious blood. Mikey's mouth and eyes were tightly shut, as if to prevent himself from both seeing what Donnie was doing and from screaming out loud from it. Leo swallowed uncomfortably, finding it harder to watch Mikey being subjected to the treatment than being on the receiving end of it himself. It felt like forever before Donnie finally started to retract the sharp, invading instrument from their little brother's body.

"There, that wasn't so bad, was it?" Donnie comforted him, as the thin metal slipped out and left a small red mark on the turtle's light-green skin.

Mikey's eyes and mouth were still firmly shut, but he answered the question by swiftly shaking his head in an inconclusive way. Donnie observed Mikey for a moment before reaching for something in his pocket, and then picked up a pink lollipop. Donnie waved it invitingly in front of Mikey. But since the younger turtle refused to open his eyes, the generous offer was completely lost as an act of futility.

Donnie waited patiently for a minute before giving up and putting the candy back in his pocket. He gave Mikey a sympathetic look and instead patted him on the head, similar to when you reward an obedient pet. He left for the desk with his newly acquired sample, and almost absentmindedly picked up the candy again to put it in his own mouth. As he reached the working area, he suddenly halted his steps and looked around for a second.

"… Oh, sewer apples," He suddenly sighed in annoyance.

"What is it?" Leo asked, with a raised eyebrow.

"Nothing, nothing," Donnie explained, with a face that heavily contradicted his words as he irritably rummaged through his desk and drawers. "... Just that feeling of dissatisfaction when you finally got the sample you wanted, but not enough vials to go around."

"You don't have anything to contain it in?" Leo wondered uncertainly.

"I _did_, until Mikey redecorated the floor with it," Donnie elaborated, with a gesture to the mess at the smaller table.

"That's too bad," Leo claimed, but couldn't help but smile.

"I'm gonna have to refill yours with his as I use them up," Donnie reasoned, as he found a small beaker and decided that it was sufficient enough to hold his booty. "That's not gonna be tedious at all..."

Donnie made a tired sigh when he finished transferring the syringe's content, and gave the blood-filled beaker a skeptic look. He then grabbed a piece of tape, wrote something on it, and then stuck it to the side of the improvised container. It said "Mikey's blood" on it, underlined three times as if to emphasize what it was.

He then put the container away, brought out his journal instead, and started scribbling in it with tetchy hand-movements, as if he had an urge to vent his frustration to something. Leo turned to Mikey instead. The turtle had opened his eyes, and was now staring at the puncture wound. The look on his face was similar to that of a chef that had found a cockroach in his kitchen. A five feet tall cockroach, wearing an apron and matching hat. It was just wrong in every way possible and most certainly not supposed to be there.

"I can't do this again bro," he shared with Leo in a queasy voice. "I can't, I'm gonna freak out. And I mean like totally lose it! I'm not cut out for these kinds of things...!"

"Just calm down, okay?" Leo told him, trying to sound reassuring. "Nothing's gonna happen to you, we'll get out of here before you know it. Our most powerful weapon right now is time. Donnie can't keep this up forever. He never had a full night sleep and he's been working non-stop since yesterday. That's our advantage; we just need to find a way to use it."

Mikey nodded eagerly to show that he understood, and then furrowed his brow in concentration. He looked up at the ceiling and then to the sides, as if he was expecting to find an ingenious escape plan somewhere in the room. He then seemed to come to think of something and turned to Leo in excitement.

"I know! Have you tried screaming for help?" Mikey suggested enthusiastically.

"No, I haven't," Leo sighed, showing little interest in Mikey's proposal.

"You _haven't_?" Mikey repeated in shock, and stared at his brother as if Leo just had ordered a pizza with no peperoni and extra 'moron' instead.

"No, because I don't think it-"

"HEEEEEEELP!" Mikey bellowed from the depths of his lungs. "MASTER SPLINTER! RAAAAAPH!"

The sudden noise made Donnie jump and accidentally tear a hole in the page with the sharp pen. He dropped the writing tool and quickly covered his ears in anguish. Leo wished that he could do the same. Leo and his brothers had often joked about how Mikey was the only one who could consider his voice an effective weapon, but never realized how close to the truth they actually were.

Leo glanced at Donnie and noticed how the taller turtle had closed his eyes tightly, as a sign of great discomfort. He then moved his left hand from the protecting position over his ear to his temple instead. It looked like his head hurt. And the pain was apparently far worse than the agony of listening to their screaming little brother. Leo studied Donnie for a moment, not sure whether the headache was caused by Mikey or possibly something else.

"Okay, okay, Mike- Mikey! You gotta stop that. Stop- Please stop screaming…!" Donnie said in a firm voice, but then raised it a notch in order to be heard. "Mikey, pipe down! I can't work like this…"

Mikey went quiet only to give Donnie a defiant look. He then inhaled deeply, preparing his lungs for an epic battle.

"… Mikey, _be_ quiet or I'll have to _make_ you quiet," Donnie explained calmly, with a tired look. "Do you understand?"

Mikey stared at Donnie with wide eyes and quickly closed his mouth. His cheeks were still filled with air, making him look like an orange clad hamster. Donnie watched him with a wary look until Mikey made a swallowing motion, turning his cheeks back to normal. Donnie made a sigh and picked up his pen again to continue where he had left off.

"… And that's why I didn't scream for help," Leo explained patiently.

"It was worth a try," Mikey stated.

"The doors are sealed shut and this place is pretty soundproof," Leo pointed out to him.

"…Still worth a try," Mikey maintained.

"Not really-"

"Dude, are you even trying to get out?" Mikey asked accusingly.

Leo didn't get a chance to answer the question as they were interrupted by the insistent ringing from an egg-shaped timer on the desk. Both Leo and Mikey stared at it in mild confusion, since none of them had seen Donnie set the device.

"Oops, I had almost forgotten about that," Donnie looked up from his notes with a surprised expression. He tossed what was left of the lollipop in the trashcan and immediately left his desk.

"Is it lunch?" Mikey asked eagerly, but then watched with a disapproving look how his brother went to the glowing water-tanks on the floor. "Dude, I thought we were done with eating algae. Unless you put it on a pizza. Oh! Leo! Do you think Antonio's have algae pizza?"

"Doesn't sound too farfetched if they count jelly beans as a topping," Leo said with an unappetizing look, but then turned his attention back to Donnie with a raised eyebrow.

"... What's he doing over there?"

Donnie had stopped by an electric winch placed right next to the closest tank, and flipped a lever to make it wind up something from the water. The machine was emitting a rhythmic, buzzing sound as it was working, and the scientist was nodding his head in time with the noise, as if it was a catchy tune. His eyes were shining with interest as the steel cable was being retracted from the liquid, bringing a massive shadow with it from the bottom of the tank. Leo and Mikey watched in unmatched shock how the body of Raphael slowly resurfaced, eerily similar to unused bait at the end of a fishing line.

His body was hanging limply from the wire, wrapped up in chains. They went all around his legs, shell, and arms to prevent any excessive movement. His arms were forced together by the restraints in a way that resembled a praying mantis. The only thing that was moving was the tails of his bandana, which dangled around his head when Donnie steered him away from the tank and lowered him to the ground. The soaked turtle hit the floor with a wet sound as he landed on his stomach. His eyes were closed with his mouth half-open in a sleeping manner, which was an alarming view, since Raph never looked this peaceful. Not even in his sleep. Donnie let go of the wire and crouched beside his brother with a kind smile.

"See?" he said in a comforting voice, as he gently rubbed his brother's back in a caring way. "I told you I wouldn't leave you in there."

"... Raph?" Mikey whispered in an unsteady voice. The young turtle's pupils looked like they were trembling at the sight.

"He's been down there the whole time...?" Leo breathed with wide eyes, his face reaching a new shade of paleness that was unrelated to blood loss.

"Huh?" Donnie answered absently, as he was busy unhooking his motionless brother from the wire. "Oh, yeah, he showed up asking for you while you were unconscious. I figured I could use him for a separate experiment while waiting for you to wake up."

"Is he alive!?" Leo demanded to know, with a stern look at the scientist.

"I don't _kno__w _yet," Donnie answered, and rolled his eyes as he removed some of the chains from the turtle. "I was just about to get my equipment-"

"Just check his pulse!" Leo ordered him in an upset voice.

"Sure, if I want to be _inaccurate_..." Donnie complained with a narrow look, but did as Leo requested and placed a finger on Raph's neck with a pondering expression. "… Hey, not bad," he mused with a pleased look at Raph, apparently finding a heartbeat. "I was hoping you could survive under water for more than 20 minutes."

He then stopped himself and scratched his cheek in a reflective way.

"Actually, it was rather expected considering that most semi-aquatic turtles can stay submerged for 30 minutes or longer depending on the water temperature. With that in mind, I probably should have expanded the time range..."

He glanced at the egg-shaped kitchen accessory on his desk, but shrugged and gave Raph an encouraging look. "We'll just have to try again later," he explained simply, as he reached for something in his pocket. "And if possible, get a timer that goes further than 50 minutes…"

"… So what do we do now?" Mikey asked Leo carefully, with an uncertain look at their leader.

Leo couldn't come up with a good answer. Up until now, he hadn't been aware of how heavily his rescue plan had been relying on the sole assumption that Raph was still out there. The fact that he had been in here ever since Leo woke up made him feel like he had let his brother down. Both Mikey and Raph.

"Uh oh…" Donnie suddenly spoke up, drawing the attention of the other turtles.

"What now?" Leo asked, and twisted his head in an uncomfortable angle to get a better view. "Is there something wrong?"

"Hang in there, buddy," Donnie continued, in an oddly calm voice, while his hands quickly removed the rest of the chains. He then grabbed hold of Raph's waist and elevated his lower midsection, making a mouthful of water escape from his throat.

"Donnie, what's going on?" Leo called out in a raising voice, fighting against his restraints with increased worry.

"Yeah, I thought you said he was okay!" Mikey concurred, with an accusing look at the scientist.

"Just because he has a pulse doesn't necessary mean that he's fit as a fiddle," Donnie clarified, as he swiftly lowered Raph's body again, and turned him over so he was lying on his back. "I think he's not breathing."

"_What?!_" Leo yelled in shock, and jerked his restraints so violently that it felt like the belts were going to saw through his skin. "Then do something!"

"Come on, Donnie! You gotta help him!" Mikey cried out in panic. "Give him VCR!"

"_CP__R_!" Leo corrected hurriedly, fiercely trying to yank free from the straps of the table. He didn't care if he dislocated an arm in the process. This had gone too far already. "Donnie, cut me loose! We have to-"

"Quiet!" Donnie exclaimed tetchily, apparently trying to listen for breaths but had a hard time doing it with all the noise around him. "I just said that he has a pulse, which means that he doesn't need chest compressions. Besides, I doubt his shell would allow me to preform them very well... "

"I don't care _what_ you do, just help him!" Leo shouted desperately.

"Since when is yelling an efficient way to secure someone's health?" Donnie pointed out in annoyance, taking hold of his brother's unresisting head and tilted it backwards slightly while lifting his chin.

"Raph, are you with me?" Donnie asked, with serious look at the red clad turtle's lifeless face. "I'm gonna attempt to resuscitate you with artificial respiration. You're probably not gonna like it, but the mere fact that you can't stop me from doing it kinda underlines the very reason why I have to."

"Is he gonna cut him open...?" Mikey asked. His face was so full of fear that he probably already had painted himself a mental image of Donnie doing it.

But Donnie did nothing of the sort. Instead, he pinched Raph's nose, and forced his jaws apart. He then made a deep inhale, and then tightly sealed his lips against his mouth. Donnie expelled the collected air into Raph's lungs two times in a row, listened for breaths for five seconds, and then repeated the act. Blow in air, listen, wait, and blow in some more. Again, and again. Leo and Mikey watched their brothers in silence. There wasn't much else they could do.

"...Good, good. Let it in, Raph, keep it in your lungs," Donnie instructed in a low voice, listening closely for a response. "Nice and slow… three, four, five, aaand one more time."

Once again he covered Raph's silent mouth with his own, forcing down the oxygen the turtle couldn't get for himself. He was just about to remove his mouth again, when a spastic movement suddenly raked through Raph's body, making the turtle vomit. Donnie quickly grabbed his brother's shoulders and made him lie on the side, wrapping an arm over him to hold him steady as a new heave made him hurl for a second time. Leaving a mix of stomach-content and algae-water on the floor. Leo cringed at the sight and Mikey made a sound of poorly concealed disgust, but Donnie seemed weirdly unfazed by the pool of smelly goo. Instead, he put a finger in Raph's mouth to clean out the remaining vomit, making sure that none of it was obstructing the airways, and listened closely for any signs of independent breathing.

"... _There_ you go." Donnie said encouragingly after getting the confirmation he wanted, and smiled brightly as he patted Raph's arm in an affectionate way. "I knew you could do it. But next time, try not to swallow so much water, okay? I doubt either of us would like to go through this again."

Raph didn't answer Donnie. He was gasping weakly and didn't make any attempts to move or talk at all. The only thing that indicated that he wasn't completely unresponsive was the hint of anguish written on his exhausted face. Donnie carefully left his side and went over to one of his junk piles. He picked out a fold-able cot with a stained foam mattress from the collection, and then wheeled it over to the unmoving turtle.

"Is he gonna be okay?" Mikey asked worriedly, his eyes fixed on Raph like a telescope on a distant star.

"Don't worry guys," Donnie said reassuringly, as he with some difficulties unfolded the bed and placed it next to Raph. "He'll be fine in two shakes of a turtle's tail, I promise."

"How can you promise that?" Leo asked with an upset look at Donnie.

The question went unanswered, as the scientist with some trouble managed to lift Raph and place him face down on top of the mattress. After making sure that the turtle's position was pleasing to him, his hands went for his pockets and came back with some orange cam-buckle straps, which looked like they had belonged to a trailer at some point in history. He used the straps to secure Raph to the bed, similar to how he had secured Leo to the table.

"Donnie, this is _not_ gonna end well. You have to realize that," Leo said sternly, underlining every word he said with authority. "This has to stop _now_, before you seriously hurt someone…!"

"Yeah, I think this was partly my fault," Donnie admitted with a little sigh, as he casually stretched another strap tightly over Raph's back. "I should have waited with submerging him until I was certain that the effects from the drug wouldn't compromise his ability to stay under water. Though, knowing Raph, I doubt that he would have given me any inclination that he wasn't feeling up for the test even if I had asked him."

"You _drugged_ him?" Leo repeated, his eyes growing to the size of tennis balls.

"It was a _mild_ _m__uscle relaxant_," Donnie pointed out and rolled his eyes. "And I didn't have much of a choice, now, did I? Have _you_ ever seen Raph help me out with something I thought was important? You know, without smashing it to pieces first..."

"That doesn't make it right to drug him!" Leo argued with gritted teeth. "He almost _died_!"

"He stopped _breathing_, there's a huge difference between the two," Donnie clarified, as he pulled at a strap to make it tighter around Raph's midsection. "Studies has shown that turtles can live a remarkable long time without oxygen without sustaining any bodily damage, so this water-test is actually well within my 48,9 limit."

"Your limit...?" Leo asked with an agitated glare.

Donnie rummaged through his pockets again, and was soon rewarded with a festive penlight that must have originated from a very old vending machine.

"I want to avoid any experiments that would seriously jeopardize your lives. So I've decided that every test I make must have a mortality rate of 48.9 percent or lower," he explained, as he leaned closer to Raph's head with the tool. "For safety reasons."

"How can you call that safe...!"

"Because it is," Donnie said in a self-evident way, while forcing Raph's eyelids apart and aimed the beam of light at his pupils to see if they responded. "I have to ensure that you guys will be okay. Therefore, the risk of a deadly outcome _has_ to be lower than 50 percent to be of equal value to the results. I could have set the limit at 49,9 percent, but that sounded a bit too arbitrary..."

"And what happens if you fail?" Leo asked, with a dark look at his brother. "What if one of your experiments goes wrong anyway?"

Donnie looked up momentarily from his examination of Raph. His face was hard to read.

"... Then I'll just have to be more careful next time," he said with a slight shrug, and gently pried open Raph's other eye to do the same procedure.

* * *

><p><strong>Next Time<strong>: A sudden change in Donnie's condition gives Leo an idea of what is going on with his brother and the cause to his strange behavior. Meanwhile, Raph wakes up from his near-drowning experience, and isn't feeling too great. But in the loving care of Dr Don, what is there to worry about?

_(__**Note**__: I do A LOT of research when writing this story (like:, reading up on medical terms, procedures, tools, turtle anatomy, etc). But I feel the need to point out that if you find yourself in the position where you have to resuscitate someone from drowning; don't use Donnie as a model. Mostly for two reasons: 1) You SHOULD perform CPR even if you can feel a pulse, since studies show that people SUCK at checking pulses. So better be safe than sorry. 2) Things get complicated when the victim has a shell, like doing chest compressions or check if the chest is rising when you blow in air… But other than that, Donnie is being very accurate. However, if you ever get the opportunity: learn CPR. It's an incredible asset in a pinch, and you might just save someone's loved one. Or turtle._


	5. Chapter 4: That's what brothers are for

**Author's Note: **Had to do some extensive research for this one, but now it's done! :D I hope you'll like it. I must admit, it was fun to finally get to write Raph again. And now I can't wait to finish chapter 5! Things are about to happen that I'm really glad Raph is around for... ;)

_And as always, if you find anything grammatically iffy or ANYTHING weird in the text at all… Don't hesitate to tell me, and I'll fix it in a flash. ^^_

* * *

><p><strong>Chapter 4: That's what brothers are for<strong>

"Not bad..." Donnie commented slowly, watching closely how the pupil in Raph's green eye went from big to small at the teasing light. "Your pupillary responses appear normal, respiration is still holding up, aaaand..." He stretched out the word as he finally allowed his brother's eye to close and instead let a finger gently rest on Raph's neck.

"... your pulse is getting stronger. Alright. All in all, it seems like you're gonna make a full recovery."

"He doesn't look very 'recover-y'..." Mikey pointed out while observing his brother's limp body with an uneasy look. Despite Donnie's assurance, Raph hadn't displayed any strong signs of life at all, except from some heavy gasping when his breathing had kicked in again.

"Do you have any idea of what you've just done?" Leo asked Donnie, and shot his brother a glare. Leo was still tightly secured to the table, unable to move. One part of him was almost grateful for that. He had known Donnie for his entire life, but this was the first time he had ever felt an urge to actually hurt him.

"Progress?" Donnie suggested, while keeping his finger firmly on Raph's neck a little longer. "I've just proved that a mutated turtle can stay under water for at least twenty minutes without sustaining any serious damage or cardiac arrest, which is nothing less than-"

Donnie caught a glance of Leo's face and flinched at his leader's dark look. He made a nervous laugh and used his free hand to scratch his cheek. "Sorry, was that a rhetorical question…?"

"He almost _drowned_!" Leo snapped.

"Relax, I had everything under control," Donnie laughed light-heartedly, and removed his hand from Raph's neck. He looked down at his sleeping patient with a smile and gave him a reassuring pat. "I wasn't gonna let anything happen to him."

"You trapped your own brother under water for over _twenty minutes_," Leo continued, trying to mentally drill the meaning of every word into Donnie's skull. "And you couldn't use _one_ of those seconds to think about what you were doing to Raph? Can you even imagine how horrifying this must have been for him? He could have died, Donnie! How can you _possibly_ justify this?!"

"I've already told you," Donnie's voice was somewhat strained as he tried to move the bed closer to his desk. The task proved to be more difficult than expected since one of the wheels appeared to be stuck and made the transport insist on turning left. "I need to study the mutagen's effects before I can estimate how to make a successful retro-mutagen. Part of that is to analyze how far advanced our own mutations are. Like, for example, figuring out how superior we are to our original specie. I might even find out whether we derive from the Diamondback terrapin or the common box turtle- "

"_That's_ why you sunk one of us into a water-tank?" Leo interrupted, with an agitated look. "How is any of that supposed to help you create a retro-mutagen?"

"I'm not sure yet." Donnie scratched his neck with an honest look at Leo. "I don't think it'll be _un_-helpful, though."

He finally deemed the bed to be close enough, and left Raph next to his brothers. He then strolled over to one of the piles of junk, and kicked some trash aside before picking up something. It was a portable tank, with a tube and a mask attached to the opening. There was a chemical symbol written on the side. Leo thought it looked like "O2", but he couldn't be sure. The purple masked turtle swiftly brought the container over to the unresponsive turtle.

"I swear, Donnie, if you're about to experiment on him again..." Leo growled threateningly at the scientist.

"It's just oxygen supplement, it's not gonna hurt him," Donnie stated tiredly, as he put down the stuff right next to the red-clad turtle. "Stop busting my shell, I know what I'm doing."

Donnie leaned over Raph and used his sleeve to wipe off some remaining vomit from his face. He then gently strapped on the mask, making sure that it covered the turtle's mouth and nose as much as possible. The size and design of it clearly indicated that Donnie hadn't gotten it from a people-clinic.

"It's not exactly a perfect fit, no surprise there…" Donnie observed, with a thoughtful look at Raph's dormant face. "But it should help him wake up faster. He'll be back on his feet in no time. I should probably take this opportunity to record my progress in my journal... Oh, and I could totally use that box with pro-markers I found to make a pie-chart! I wonder in which pile they ended up in..."

He straightened up to go look for the drawing tools, but stopped as he noticed a shiver from Raph. Almost as if a cold wind just had passed by in the sealed off lab. Donnie studied Raph's damp body for a moment. He then went over to another pile of junk, managed to free a striped, tattered bedspread from the trash, and came back with it. He wrapped the improvised blanket over Raph, smoothed it out over him, and gave him pleased smile before he left his side again.

"... I still don't get it," Mikey admitted, almost going cross-eyed from staring at the tall turtle. "Is he, like, a crazy Donnie, a bad-guy Donnie, or the _real_ Donnie who's just having a weird day?"

"It shouldn't be this hard to tell, right?" Leo agreed, and made another attempt to pull his right arm free. It almost felt like the straps were getting a little loose. "There has to be a way to get out of here somehow. And fast. Before he gets some new mad idea, like... I don't know. Like finding out whether our shells are fire resistant, or what kind of splatter-mark our bodies would make if he dropped us from a fifteen-story building..."

"Whoa… Dude, I know!" Mikey exclaimed in a sudden light-bulb moment, and turned to Leo with a wily smile. "Do you think I can make this thing fly if I spin my legs super-fast? You know, like a helicopter?"

"Do _you_ think that?" Leo answered his youngest brother with a pedagogical voice. The older turtle's face was a picture of doubt.

Leo's question caused Mikey to hesitate. Then he quickly started to spin the chair with his legs out like rotor blades, reaching an unrealistically high speed, but sadly without leaving the floor even a little. The freckled turtle's head wobbled with a dizzy expression when the revolving chair started to slow down.

"Wait, wait! I didn't try hard enough!" Mikey assured Leo, with a determined look, and made another attempt to pick up speed again.

"Ungh...!"

The unexpected sound made Leo and Mikey look up, their eyes immediately falling upon Donnie. The turtle was still digging through a pile of junk, but was now also clutching his head with his left hand. His expression wasn't far from how Leo had imagined his own face every time the needle had penetrated his skin. As if the scientist was trying to ignore a sudden sharp pain.

"… Donnie?" Leo asked with an uncertain look at his brother.

"Is he having a brain-freeze?" Mikey asked curiously, and then turned to Leo with his own interpretation of a discrete voice. "Cause I don't see any ice cream, and now I'd really like some."

"Hey, are you doing okay...?" Leo asked Donnie with a puzzled look, not sure what to think of the situation.

"Yeah, yeah, no problem. I'm sure I put them here somewhere..." Donnie assured him absently. He blinked hard a couple of times, as if to regain focus, while picking through the trash with his free hand.

"I'm not asking about the markers." Leo shook his head softly.

"What? Oh, right. Of course not," Donnie answered, with an apologetic glance at the leader. "I just… I guess I'm a little- OUCH!"

Donnie suddenly wrapped both his hands around his head with an agonizing look and dropped to his knees. As if someone was beating him, and he was desperately tried to protect himself. He shut his eyes tightly, clearly in pain. Judging from his tormented face, nothing he did seemed to fend off his invisible attacker at all.

"Donnie, what's going on?" Leo felt the need to ask. He didn't care that he just a couple of minutes ago had wanted to hurt Donnie. Nothing of that mattered anymore, and the only thing he felt right now was genuine concern for his brother.

"Yes. Or no. Both. Maybe..." Donnie answered, completely unrelated to the question, as he unsteadily got up from the junk pile."… sorry. I have no idea what I just said. I... I- I think I'm having a stress-headache..."

"Can I get you something, bro?" Mikey offered kindly, but quickly realized that he couldn't leave the seat. "Oh, right... Um, anything I can reach with my toes?"

"Just... I just need a chair," Donnie breathed heavily. His face winced as the pain suddenly spiked. "Or a floor. Just about anything with basic supportive properties would be nice..."

He interrupted himself with a shout of agony, momentarily losing control of his legs and almost collapsed to the ground. It was by pure luck his hands managed to grab the desk, making him hang from it like a drowning person to a boat. He dragged himself back up on his feet, and with great difficulty made it to his chair. He sat down in front of his desk, his hands cradling his neck, while trying to endure the pain with deep breaths.

"I don't think that's a stress headache, Donnie," Leo concluded with a serious look. "I'm betting it's related to why you've been acting so weir-"

Leo suddenly noticed how Donnie's calm deep breaths were inhaling the fumes from the boiling mutagen jar. The smoke was thick and green, and you could clearly see strings of it enter the turtle's nostrils. For every breath Donnie made, his face looked less distraught, as if the fumes had a soothing effect on his rampaging head.

"… Huh. What do you know," Donnie suddenly spoke, with a look of mild surprise written on his face, before making a soft chuckle. "I think it just passed. Wow, that's a relief. It's kinda hard to concentrate when it feels like someone is firing a nail gun inside your brain."

"… Donnie, what is that jar over there?" Leo asked. His eyes were locked on the object in the same manner a dog watches an intruder.

"I'm pretty certain I've already mentioned that at some point," Donnie noted, but scratched his cheek as if he wasn't certain.

"You said it was a 'project on the side'," Leo reminded him. "What kind of project?"

"Nothing important," Donnie said with a dismissive wave, as he grabbed something in his pocket he thought was a pen, but turned out to be another lollipop. He blinked at the curious mix-up for a second, but then casually put it in his mouth and picked up a new writing tool. "I'm mainly just monitoring what it does."

"And what does it do?" Leo asked patiently.

"Boiling. Mostly." Donnie observed, while scribbling in his journal.

"You have to get rid of it," Leo told him urgently. "I think the fumes are messing with your head. Think about it, it's boiling _mutagen_. There's no way that stuff can be good for you, and it's probably what's making you do all these things. Don't you see?"

"It's kinda funny that you'd say that," Donnie shared with an amused look at Leo, as if he found his brother's opinion fascinating. "because, naturally, I also assumed that the fumes were harmful when I first initiated the experiment."

"And what changed your mind...?" Leo asked, with a doubtful look.

"When I woke up this morning and discovered that I've been sleeping right next to it for an hour or so," Donnie explained and shrugged. "See? I've been breathing this stuff in my sleep, and I'm no worse for it. I'm working on a theory that mutagen loses most of its properties during the phase transition from liquid to gas-"

"You're telling me that you haven't noticed _anything_ different about you since then?" Leo wondered, with an extremely questionable look at his brother.

"Nope. Well, now that you mention it..." Donnie added, and glanced at the ceiling with a thoughtful expression while sucking on the candy. "I can't be absolutely certain, because my IQ was already pretty high to begin with, but I think I'm actually getting smarter. It's hard to describe it, but I've been coming up with some ideas recently that I don't think even _I_ would have thought about."

"Maybe because a _normal_ Donnie knows that it's _off the charts insa__ne_ to experiment on your own family!" Leo agitatedly pointed out, and made another attempt to free his hand. "How exactly are you gonna explain our absence to Master Splinter when he wakes up?"

"I... haven't thought that far ahead yet." Donnie blinked, in sudden realization.

"… You haven't?" Leo asked, with a raised eyebrow. He was so taken aback by the answer that he for a split second thought that Donnie must be joking.

"No," Donnie confirmed, and turned to Leo with a puzzled look. "What? Is it that surprising?"

"Kinda." Leo shrugged slightly. "You tend to be a 'thinking far ahead' guy. You made a submarine before you even knew we would need one, remember?"

"Yeah, I guess you're right," Donnie admitted, and tapped his chin with the pen. "Sensei must have slipped my mind while I was busy working with you guys. I'll be back in a flash."

"No, wait... Donnie!" Leo tried to stop him, but the turtle had already left the desk and disappeared through the garage doors. "Great... That's just perfect."

"Sooo, did he do something to Master Splinter, or what?" Mikey asked, with a clueless look. The freckled turtle was clearly not a keen listener, and apparently hoped that his older brother could fill him in on the details.

"Sai..." a low, muffled voice uttered beside them.

Both Mikey and Leo's eyes widened at the sound. Leo quickly looked at the camp-bed, and Mikey turned his head so fast that it was a miracle he didn't snap his neck. Raph's radiating green eyes were blinking drowsily, his face partly hidden behind the oxygen mask. His fingers seemed to search for his weapons by pure instinct, but the attempt was futile because of the restraints.

"Raph!" Mikey called out with a beaming smile. His sky-blue eyes were fixed on his awakening brother. "He's back! Leo, he's back! Raph's awake!"

"Glad to see you, Raphael." Leo smiled in relief, feeling like a stone had been lifted from his chest. "Are you okay?"

Raph made a grimace of discomfort, and violently coughed up some water in the oxygen mask. The effort left him panting weakly on the bed with a tired look. If he ever intended to answer Leo's question, he couldn't bring the energy to do it right now.

"I feel _exactly_ the same, bro." Mikey said, with an understanding nod.

Leo observed the red-clad turtle with a worried look. However, Raph seemed to quickly recover from his coughing fit, possibly out of pure stubbornness. He soon started to stretch the straps with a determined expression. Trying to move his arms and legs from their trapped position in any way he could.

"Don't tire yourself out, Raph," Leo advised. "You should save your strength until you-"

Raph made an intimidating growl as his muscles tensed up. He started pulling at his restraints again. The straps were tightly secured around his body to hold him down, and unfortunately they were doing a very good job. His breaths sounded strained, but there was nothing in his movements that suggested that he was planning to stop. Instead, the force in his struggle seemed to grow even more intense at a terrifying rate. It looked like he expected the buckles to give in out of sheer fear of him.

"…Or why don't you just ignore me," Leo said with a sigh. "That works too..."

"I'm just..." Raph replied with gritted teeth, trying to turn his torso to free his arm. "Nng... gonna...! _This_...!"

After an admirable extended battle with the opposing team of cam-buckle straps, Raph finally ran out of juice and collapsed on the cot again with a frustrated groan. His body was heaving from the heroic attempt, while his narrow eyes were aimed straight forward. He didn't look defeated. He just looked extremely pissed off.

The remaining turtles stared at him with a tense silence building up in the air.

"You're sorta tied up." Mikey helpfully informed.

"I got that!" Raph barked with an agitated look at his youngest brother, but his grumpy face soon changed into a queasy one instead. "Man, I feel like I've eaten something bad... My tongue tastes like moldy cheese and rotten vegetables."

"More like algae and yesterday's pizza," Leo corrected, and glanced in the direction of the water tank. "At least judging by the look."

Raph looked over at Leo with a puzzled expression, before he followed his eyes and discovered the pile of vomit a couple of feet away from them. He turned his face away with a disgusted sound.

"Great, _just_ great..." Raph exclaimed bitterly. "'Cause knowing what it _used to be_ makes it tastes so much better..."

"Do you remember what happened?" Leo wondered, and observed Raph closely. "You know, before you went down that thing?"

Raph froze at the question, his pupils shrinking in size. He didn't answer Leo, and looked away with an unreadable expression. Leo wasn't sure of how to interpret Raph's reluctance to talk. He guessed that Raph either simply didn't remember anything from the incident, or he remembered everything, but rather wished that he didn't.

"It's fine, you don't have to tell us," Leo quickly assured him, feeling that this was a subject better left untouched for the moment. "The important part is that you're alright."

"Don't worry bro," Mikey happily announced. "I'll get you up to speed on everything you missed out on while you were gone. Let's see... Um… The TV-remote is broken, then it got _super-broken_, I fell on it. Donnie doesn't know how to fix it, and Leo has doodles all over his shell. We have an electric saw now, by the way, and Donnie has become some sort of-"

"_Mikey_, shut it...!" Raph groaned in irritation, and made yet another try to escape his captivity, but without success. "This totally blows! I _knew_ I should have punched that dork harder at training. A good old concussion would've set him straight..."

"Could we try to stay focused on the situation at hand?" Leo suggested with a firm look at both his brothers. "Right now, we need to work together. With all three of us, we should be able to come up with a plan that will get us out of here."

"Oh yeah?" Raph coughed after another failed attempt to break free, but still somehow managed to give Leo a teasing smirk. "How's that working out for ya'?"

"Hey, I've only had like 2 minutes to think of one," Leo argued with a defensive look. "Cut me some slack, I was counting on you busting us out. At least right up until Donnie fished you up from that tank."

"Well, that plan sucks!" Raph retorted, with an angry cough.

"Don't worry. I'll think of something," Leo assured Raph, and looked around him to get any ideas.

"Wait, what about Master Splinter?" Raph suddenly asked. "Isn't he around?"

"No can do." Leo shook his head. "Donnie put something in his tea, and apparently, not even _he_ knows how long he'll be out."

"He drugged Splinter too?!" Mikey exclaimed, dropping his jaw in shock. "Oh man, we're doomed… We're so doomed!"

"So I guess you forgot to tell Mikey about that part, huh?" Raph said casually, not even bothering to look at the freckled turtles exaggerated reaction.

"I assumed that he'd figured it out by himself when Donnie said he'd go to check on Splinter, not even Mikey should be able to miss that," Leo explained with a tired sigh.

"Did you just use _'Mike__y'_ and _'figured it out'_ in the same sentence?" Raph asked with a doubtful look at his brother. "You see, it's choices like these that make me question you as a leader."

"Thanks for your input," Leo answered dryly, but then realized something."… Donnie doesn't know that you're awake yet. We should try to keep it like that for as long as possible."

"What, you mean like playing dead?" Raph remarked, with a provoked look at Leo. "Heck no! What kind of wuss-plan is that?!"

"What Donnie doesn't know is an advantage to us right now," Leo clarified, and tried to sound as reasonable as possible. "If he thinks that you're still unconscious, he might let his guard down and give you an opportunity to escape."

"Have you _met_ me?" Raph asked, and almost made it sound like a sincere question. "When I get an opportunity, I'm not using it to escape. I smash stuff!"

"Fine! Do that!" Leo caved, with a frustrated groan. "Whatever suits you the best. But _please_, just lie low for a while and wait for-"

There was a sound at the entrance, and Leo looked up just in time to see the purple-clad turtle come into view again. He was busy chewing up the last pieces of his lollipop when he suddenly noticed three pair of eyes staring at him.

"Hey, look who's awake," Donnie commented cheerfully, his eyes quickly singling out Raph from the crowd, and set his track for him.

"Well there goes _that_ plan..." Leo mumbled, with an annoyed look at the green-eyed turtle, who quickly returned the favor with an equally annoyed glare at the leader.

"How do you feel?" Donnie wondered, as he reached his side.

"Like stabbing something," Raph replied casually, and fixed his eyes on Donnie like guns ready to fire. "Your face would make a good bulls-eye."

"I'll... take it that you're feeling better then...?" Donnie asked, with a wary look at the threatening turtle. He was still gnawing on the depleted candy stick as if he hadn't decided what to do with it yet.

"And _I_ take it that Splinter hasn't woken up yet?" Leo deduced, with a bitter sigh.

"Doesn't look that way," Donnie turned to Leo with a small shrug, and rubbed his neck in an uncertain manner. "But it was kinda hard to tell. Curiously, it's very difficult to spot the difference between a person in a deep meditative trance and someone who's under the influence of a strong sedative. I couldn't even bring myself to poke him just to make sure."

"Glad to hear that you haven't gone _completely_ insane yet..." Leo muttered sarcastically, with a crooked smile.

"I'll just have to check on him later," Donnie reasoned, and then turned his attention back to the brother with the most attitude. "And you need a follow up, by the way."

"How about you loosen these things first, and then you can follow up my fist when it punches you in the guts?" Raph suggested politely.

"Wow, I can already sense that this is gonna be a hoot..." Donnie concluded with an unhappy look at Raph, as if he just had been dealt an unsatisfactory hand in poker. Raph, on the other hand, looked like he wouldn't hesitate to bite off Donnie's fingertips if he got the chance.

"Better you than me, bro." Mikey smiled, for once looking rather pleased with his restrained position.

Donnie sighed as he took out the stick from his mouth and put it in his pocket. He bent down and carefully removed the oxygen mask from his brother, not unlike someone who's removing a muzzle from a devious pit bull. He then unexpectedly turned to Leo with a wondering expression.

"Are you feeling better?" Donnie asked, out of the blue. "No lightheadedness, nausea or anything?"

"Not what I know of?" Leo replied, but couldn't help but to add a question-mark to his answer.

"In that case, would you mind lending your analyzing-cuff to Raph?" he elaborated, and pointed at the contraption that was still attached to Leo's right arm. Leo had almost forgotten about it.

"_You_ are the one made me wear this thing to begin with…!" the leader exclaimed in annoyance.

"Is that a no...?" Donnie wondered with an awkward look, as if he understood that Leo didn't want to be separated from the gadget.

"Take it," he simply stated, and looked away indifferently.

Leo soon felt a slight chill as the scientist removed the cuff from his skin. Donnie then went over to Raph to attach it to him instead, but recoiled when the turtle suddenly made a violent jerk as if he was going to attack him. Donnie looked at Raph with an unamused glare, while Raph grinned like someone who just got his birthday-wish."

"Real mature, Raph..." Donnie huffed, as he made sure that the cuff was properly secured before leaving his brother to check the computer.

"Any time," Raph answered with a rather pleased smile, which was only interrupted by another cough.

"Was that a wet cough or a dry cough?" Donnie suddenly asked, and observantly looked up from his laptop like a meerkat that had detected a suspicious sound.

"It was a 'shut your yap' cough," Raph informed, with a glare that strongly advised his brother not to ask for the details.

"It was a wet one, wasn't it?" Donnie concluded firmly, not taking any notice of Raph's hostile tone. The red-clad turtle just kept glaring at Donnie, but eventually turned away his eyes in a dismissive way.

"What are you thinking about, Donnie?" Leo suddenly asked, with an uncertain look at the brooding scientist.

"I'm thinking that it's probably just residual water..." Donnie shared, but his serious face didn't match his reassuring words. "Well, most likely, anyway. But it does remind me of something else."

He left his chair and started to search the area around his desk by moving some books and notes out of the way. Leo couldn't remember last time he had seen Donnie's work desk this messy. It wasn't just covered in books and sheets of papers, but also glass beakers, colorful wires, several vials in different sizes, and a lime green lollipop which Donnie seemed to almost absentmindedly pick up and put in his pocket. When he didn't find what he was looking for, he went on to checking the cardboard boxes on the floor instead.

"What's he doing now?" Mikey wondered curiously, apparently aiming the question to Leo, but made sure to say it loud enough for Donnie to hear.

"Raph needs an antibiotic shot to prevent infection," Donnie explained, and after some digging finally found a smaller box. As he opened it, the box turned out to contain various kinds of tiny bottles. "It's standing procedure after a near-drowning incident, since pneumonia is a common complication caused by submersion. I'm pretty certain I got my hands on some rocephin when I was browsing today... Aha! Got ya'."

He triumphantly held up a small bottle with a clear liquid. He put it on his desk with a pleased smile as he went to rummage through a drawer instead. "It needs to be injected into a muscle," he continued as he retrieved a new syringe. "so it shouldn't be a problem to apply it."

"Does he really have to be tied up for that?" Leo wanted to know, and glanced at his restrained brother. "You could loosen the belts a little, you know. He almost drowned. Plus, keeping him strapped down like this kinda adds to the whole 'mad scientist' persona you got going here. Which you still claim is all in our collective imagination..."

"I know what it looks like, but I don't have much of a choice in this case," Donnie explained, as he filled the needle with the bottle's content. "Rocephin has a very dense quality, so it has to be passed slowly through the needle, which naturally makes it take a while to administer. And it's important that he lies still the whole time. Let's see..."

He pulled out the needle from the tiny bottle and held up the sharp tool in the light, flicking it with a finger and squirting out two drops to get rid of any lingering air bubbles. "Also, according to certain internet forums I've encountered, some people claim that the injection can be fairly painful."

"You're _not_ putting that inside me..." Raph growled threateningly as Donnie approached him with the antibiotics, his whole body tensing up like a cornered animal about to lash out.

"You'll be fine. It's just an intramuscular injection, I'm sure you can handle it," Donnie assured him with confidence as he settled down by Raph's lower midsection. The angry turtle followed his every movement with deepest detest. "Now, try not to move. If I accidentally hit a vein, we'll have to do this all over again..."

Raph's fists were clenched as if they were longing to strike someone really, really hard. But Donnie seemed too occupied with the syringe to notice it. He removed the improvised blanket from Raph's body, and jabbed the needle in his thigh muscle with a quick thrust. Raph visibly winced from the action, but didn't allow himself to make a sound. Donnie aspirated the needle before he slowly started to pull down the plunger.

It was almost peaceful. Mikey and Leo were watching in silence, unable to find anything appropriate to say. Raph had tightly shut his jaws together and refused to utter a word out of spite, but Donnie was completely immersed in the task of releasing the syringe's content into his brother's body. Nobody said a thing. At least not in the beginning.

It was approximately after the first ten seconds that Raph suddenly let out a muted groan and started squirming, as if to get rid of the intrusion. But Donnie had a firm grip on his secured leg and didn't let him shake off the needle.

"Easy now, Raph, easy..." Donnie soothed calmly, still applying pressure to the plunger. "Don't fight it, I'm just doing this for you own good, okay? This will help you."

"Take... it... _o__ut_...!" Raph ordered through gritted teeth, his breathing quickening as his struggles grew more intense.

"I can't do that," Donnie informed him with a serious face as he tried to keep the limb steady. "Just hold on, I'm not done yet."

"Knock it off!" Raph shouted at him. His pupils shrunk noticeably in size as his desperation grew.

"Relax, you can do it, buddy. Just a little longer..." Donnie kept coaxing, his eyes fixed at the gauge on the syringe's barrel. Only half of the liquid had been injected so far.

"Come on bro, let him go already!" Mikey angrily called out in a protective manner, and made his chair twist and turn to emphasize his demands. "You're not making him better, you're just hurting him!"

"I think you should stop it, Don," Leo said, with an uneasy look at his suffering brother. "Mikey's right. He isn't doing too good..."

"Don't worry, it's almost over," the scientist reassured him, but somehow failed to make it sound very convincing. "I know it hurts, Raph. Just bear with it, okay? You're doing great..."

Raph had closed his eyes tightly and slammed his head down on the bed repeatedly to silently endure the anguish. However, the mattress didn't allow him to cause himself any self-inflicted harm to distract him from the pain.

"Almost there..." Donnie announced softly, with his tongue out in concentration.

"…_S__t__o__p,_" the turtle pleaded, with a strained voice. His eyes were still closed in distress as he bit down on the padding in order to maintain some sort of control.

"Just a liiittle longer..." Donnie continued slowly with narrow eyes, as he with great interest watched the plunger reach the end.

Raph screamed down into the bed's padding in unrepressed excruciation. He hid his face in the fabric, pressing down his head as hard as he could to wait for the torture to be over.

"... Done," the scientist finally declared, and gently let the needle slip out from his brother's tormented limb. He turned to him with a comforting smile. "I knew you could do it, pal."

The injection had taken almost two minutes to complete. Raph was still panting heavily from the experience, sounds of pain escaping from him with every breath he took. Donnie gave his shell an affectionate stroke before leaving his side. He went back to his desk, but gave the syringe a somewhat suspicious look.

"I'm really sorry for the discomfort," he apologized as he studied the medical tool in his hand warily, as if it alone was responsible for his brother's suffering. "The label _did_ recommend mixing the antibiotic with a diluent to make the solution less concentrated and easier to administer. But since they made it sound optional, plus I couldn't find one that didn't contain calcium, I kinda assumed that we wouldn't need one."

A muffled, pained groan could be heard from the depths of the camp-bed, and Donnie turned back to Raph with a curious glance. "I know," the tall turtle chuckled nervously and scratched his neck. "'Should have looked harder', am I right? But believe me; compared to being bedridden for an extended amount of time with fluid in your lungs, this is the preferable option. I would never expect you to thank me, but... you're welcome."

He went back to his desk to discard the used needle, but quickly caught the sight of Raph's partly buried face. The headstrong turtle's features were contorted in silent agony. His body was still heaving heavily from suppressed pain as he bravely tried to hide his anguish from his brothers. Donnie watched Raph carefully as he left his desk and walked back up to him, crouching in front of the turtle. He kept studying his hurting face with an unreadable look, as if he knew he was supposed to do something, but couldn't quite recall what it was.

"Do you want an ice pack for the pain? Or maybe an extra blanket?" Donnie finally asked in sympathy, and reached for something in his pocket before offering him it with a smile. "Lollipop?"

Raph's eyes only briefly met the candy before they rolled back behind tightly shut eyelids, refusing to resurface again. The fact that he couldn't muster enough energy to rudely deny the offer, or insult the scientist for making it, was almost disheartening to watch. Donnie observed him and raised a concerned eyebrow. He put the candy back in his pocket and then tenderly rested his hand on his head in a caring manner. Raph was trembling with contained pain and agitation, but he couldn't stop Donnie from doing it.

"Just let me know if there's anything you need, okay?" Donnie offered kindly, with a somewhat crooked smile at the red-clad turtle. "You don't have to worry about anything. I'll take care of you. That's what brothers are for, right?"

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><p><strong>Next time<strong>: An unexpected way to escape shows up, and the turtles have to work fast in order to stop Donnie from doing something he'll regret. Is Donnie really as far gone as his brothers think? And what about April…?

_**Note**__: If you're soon to have an antibiotics shot, I sincerely apologize for this chapter. I'm 98% certain that your doctor won't be Donnie, and in that case you should be just fine. I'm sure legitimated doctors consider the pain-factor in much greater regard than Donnie does right now. And more importantly, they have most likely graduated from medical school. Just remember that you're in good, capable hands._

_Here, have a lollipop. :)_


	6. Chapter 5: Hit me

**AN:** I apologize for the late update. I meant to post this days ago, but my health said NOPE and wouldn't let me leave my bed. And I ran into some problems with this chapter. First of all; it's the longest one yet (I'm so sorry…!). But here's the thing: it was supposed to be even _longer_. I've completely miscalculated the length of this chapter, which means that I had to cut off a huge part of the end and move it to the beginning of chapter 6 instead. I don't think it will affect the story, but I felt that I should tell you.

Well, I hope you'll enjoy this beast! ^-^ My favorite part didn't make the cut, and won't appear until the next chapter. But I really hope you'll stay for that! :) It's not much left now...

**EDIT**: I read that there are some concerns of where this story is heading, and I feel the need to remind you that there won't be any deaths in this fic. ^^ I won't let Donnie do something... Well, something too irreversible. And if crazy-Donnie is starting to _really_ tick you off by now, don't worry. Chapter 7 is not far away... ;)

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><p><strong>Chapter 5: "Hit me"<strong>

Mikey's gaze was almost tip-toeing over Raph's body, as if he thought a direct stare could hurt him.

The red masked turtle was still suffering from the repercussions of the rocephin injection. But it was unclear how much, since his efforts to hide his condition were nothing short of admirable. He was breathing unsteadily, changing from deep inhales to short ragged ones, as if he couldn't figure out which kind of breathing would ease his agony the best. He had persistently buried his face into the soft mattress beneath him, allowing himself a false sense of solitude in his discomfort. He only looked up occasionally when breathing through the thick fabric got too difficult. Sometimes, a sudden sound of pain escaped him, which would immediately be followed by a period of complete silence where the turtle wouldn't even let himself breathe too loud.

Mikey's big, sympathetic eyes were brimming with a compulsive need to help his brother, but he had no idea how. He wasn't used to seeing Raph like this, no one was. The hothead's resistance to pain was of legendary proportions, and Mikey knew that he would go to ridiculous lengths just to prove how tough he was. Mikey couldn't tell if Raph wanted to be comforted, hear some encouraging words, or simply be left alone. The last option seemed the least likely to result in a vicious response.

"Raph...?" Mikey carefully inquired, feeling it was his duty to at least try. "You okay there, bro? Can I do somethin' for ya...?"

The low, pained growl from the older turtle strongly implied that it took a great deal of willpower to not start yelling angrily at his little brother. He hid his face deeper into the mattress, shielding himself from the others. Like a hurt animal that didn't want to show weakness in front of its pack. But Mikey didn't seem offended though. Judging by his face, Leo could tell that this was one of those moments where Mikey actually had a situation perfectly clear to him. He knew he hadn't done anything wrong. And he knew that Raph's anger wasn't with him.

"... Do you think Donnie's being worse to Raph than to us?" Mikey asked Leo, carefully looking between the busy scientist at the desk and the green eyed turtle.

"I don't think Donnie _knows_ that he's being worse to Raph," Leo theorized. Donnie and Raph were the brothers who had the least in common, sharing only a notoriously short temper. After years of verbal and physical abuse, it was only natural if the genius had developed some level of resentment towards the violent turtle. Perhaps the undiluted antibiotic was not an act of innocent neglect as much as payback for a lifetime's worth of bullying. But even if that was true, Leo doubted that Donnie was even aware of it. If anything, Donnie seemed to be just as much in the shadows of what was going on inside his head as the rest of them.

Leo kept a watchful eye on the tall turtle, making sure that Donnie was too preoccupied to notice Leo's struggling arm. Donnie had gone back to experimenting with his brothers' blood, and was studying a sample closely under a microscope to see if it reacted favorably with his attempted retro-mutagen.

"Great… Another reject batch," he sighed, and looked up from it with a disappointed glare as he removed the glass slide to discard the useless content. "You know, considering all the enemies we've been up against so far, I never thought my ultimate adversary would turn out to be biological repair systems and chemical agents..."

"I wouldn't be so quick to decide," Leo pointed out, while weakly trying to twist his arm free. "I think Raph punches harder than your samples..."

"Yeah, speaking of which," Donnie pondered, and curiously threw a glance at the turtle in question. "How is he holding up over there?"

"He's holding _on_. And not thanks to you," Leo replied, and tried to shoot him a narrow look, but felt too lightheaded to do it very well. "What's the point in giving him medicine if it only makes him feel worse than he did before?"

"It'll pass. Just give it some time," Donnie assured Leo, with a self-evident gesture. "Though exactly how much 'time' is a little unclear at this point. Are you sure you don't want me to give you something for the pain, Raph?"

"I'll give you something for the pain!" Raphael suddenly snapped at his brother, like a snare around an animal, ready to strangle it until it stopped twitching. "I'm gonna make your shell into an open casket and _bury_ you in it! You hear me?!"

"It's kinda hard not to..." Donnie admitted and winced, indicating that the sudden rise of volume had caught him off guard. "Look, I'm asking because I don't know how long the pain is gonna last. It's a real possibility that you'll feel like this for hours, in which case I'm wondering if there's anything I can do to make you more comfortable?"

"I have an idea! Let me stab your leg with a piece of glass fifty times," Raph suggested, his eyes burning with the viciousness of a mythological beast that had awoken from its 1000-year slumber to destroy the world. "Then you can get me a bucket of water to shove that egg-head of yours into. We can call it even when ya start gasping for air and beg me to stop!"

"I really don't think that hurting me is gonna make your leg hurt less," Donnie reasoned, but scratched his cheek in an uncertain manner.

"And _I_ really think we should put that to a test!" Raph bit back, baring his teeth at his brother in an animalistic way.

Leo was almost glad that his brother was restrained, because that threat sounded alarmingly close to a promise. He had no idea what Raph was capable of doing in this state, and Leo hoped he'd never have to find out.

"Dude… I can't even remember last time Raph lost it this bad," Mikey felt the need to point out, looking almost impressed. "You know… I feel like I should talk to him or something, but I don't think I want to..."

"It's called self-preservation," Leo stated with a sigh, taking a break from his escape-attempts when his right arm started to hurt. "Stay out of it until he's cooled off, or he'll lash out at you too. If this is what he needs to do to take his mind of the pain then by all means; let Raph have his tantrum. To be perfectly honest, I think Donnie had this one coming..."

The insults and threats were hailing over the scientist like a blizzard of raw, unfiltered rage. Mercilessly trying to do as much damaged as possible, with no sympathy for the target. Donnie endured it for almost a full minute before he made a tired sigh and got up from his desk. He walked over to the furious turtle, crouched in front of him, and just when Raph was about to unleash a new collection of discourtesies, Donnie picked up a lollipop and put it in his mouth. It silenced him instantly. Like a pacifier to an inconsolable child. Raph was momentarily paralyzed by the unexpected action, but then quickly spitted out the candy. He threw a murderous glare at the scientist, who had casually walked back to his desk.

"What the _heck_ was that about?!" Raph called out, his eyes fixed upon Donnie as if he was the most hated object on the entire continent.

"I was hoping it would keep you quiet for a while," Donnie explained absently, as he stopped in front of a drawer.

"_Are you completely brain-dead?!_" Raph yelled furiously, almost turning hoarse from all the screaming.

"No, but I'm starting to feel another headache coming along," Donnie clarified, while tiredly rubbing his eyes with two fingers. He reached for something inside the drawer and came back with some sort of old-fashioned gas mask with a small canister attached to it. "I'm thinking it would be good for you to rest for a couple of minutes, don't you agree?"

"Oh no you don't!" Raph quickly exclaimed in objection, and flinched as Donnie approached him with the instrument. "No, don't you dare! Stay away from me!"

"Stay still," Donnie simply instructed, as he sat down next to his brother and covered his face with the transparent plastic. He pressed a switch on the canister, allowing the gas to fill the hothead's lungs. Raph's rapid breathing soon fogged the inside of the mask, completely hiding the turtle's features except from his panic-struck eyes.

He started twisting and turning his head, similar to a horse that refuses to wear a halter, frantically trying to get rid of the intrusive gear. But Donnie persistently kept it in place, using one hand to keep the mask on, and another to hold down Raph's resisting head.

"It's okay, Raphael. Don't be scared, it's just anesthesia," Donnie reassured his panicking brother in a calming voice. "It's not gonna hurt you, trust me. You'll feel all better soon."

Raph shook his head violently in denial, making muffled sounds in protest behind the mask. He then suddenly closed his eyes tightly in what looked like determination. Donnie promptly raised an eyebrow at him in disbelief.

"Really? You're not gonna breathe until I put this away?" he asked unamused, as if the turtle was playing a game with him that the scientist failed to see the fun in. "You know that I quite recently analyzed exactly how long you can go without air, right? You can't win this, pal. Not that twenty minutes isn't impressing, I'm just saying that I can sit here longer than you can hold your breath. If you refuse to inhale this, you'll eventually faint from hypoxia. Which, to be brutally honest, would also do the trick. Do you see where this is going?"

But Raph kept struggling, ignoring Donnie's words. He started bucking and thrashing against the restraints, but his efforts soon started to cease. His furious face was growing more worn and tired by the second, and his panting made him involuntarily chug down the gas even quicker. His eyes were blinking groggily as he desperately tried to keep on fighting, but it was a losing battle. All his remaining energy was being stripped away from him, forcing him into a submissive state where rage was an emotion that was out of his price-range. Donnie didn't even have to force his head down anymore, and settled with just resting his hand on it.

"Easy… Slow breaths. There, that's more like it." Donnie smiled, and patted Raph's head in an encouraging way as he felt his brother's tensed muscles involuntarily relax. "See? There's nothing to worry about. Everything will be fine, you're just gonna go away for a little while, okay? You won't even remember this when you wake up. Sleep tight, buddy."

Raph's eyes were the last part of his body that gave up. The eyelids slowly closed as his head finally fell to the side. Donnie kept the mask on a little longer for good measure, apparently not completely convinced about the hothead's state of consciousness. After another minute, he snapped his fingers in front of Raph's face a couple of times and parted his eyelids, looking for some kind of response. When he was certain that Raph had lost all sense of awareness, he finally closed the canister, removed the gear from the turtle, and corrected the position of his brother's head so that it was lying straight. He then picked up the mask together with the rejected lollipop, and went back to his desk to continue his research. But his expression was oddly displeased as he studied the gas mask in his hands.

"... I'm gonna need your help to keep an eye on him. I just realized that I've no idea when the effect will wear off," Donnie said, and scratched his head. "Anesthesia generally works quickly and doesn't stay in the system for long unless it's given continuously to the patient. It's possible that the dose I gave Raph will only keep him knocked out for a little while."

"So what now? You're gonna do more bad stuff to him while he's asleep?" Mikey asked, with a reproachful look at the purple masked turtle.

"First of all; he's technically not asleep," Donnie corrected, with an annoyed sigh. "General anesthesia puts you in a state that's actually closer to a reversible coma than sleep-"

"Raph's in a _coma_?!" Mikey freaked out, looking at the scientist as if he didn't just have a screw lose, but a whole bunch of them parading out from his brain through his nostrils. "That's the _bad_ kind of sleep, even I know that! Why would you do that?!"

"_Secondly,_" Donnie continued, ignoring Mikey's sudden outburst. "Stop assuming that everything I'm doing is bad stuff! Have you any idea of how discouraging that is? I'm trying to create a retro-mutagen, a cure for everyone that has been mutated by the Kraang, and you're acting as if _I'm_ the villain here?"

Mikey gave Donnie a long narrow glare. He then held up his restrained hands and feet for all to see, and looked at his brother as if to say "exhibit A". Donnie blinked at him with an unreadable look.

"… Point taken," Donnie acknowledged, but immediately dropped the subject as he started fiddling with some chemicals on his desk. "Anyway, the perk with anesthesia is that it's supposed to work as an analgesic too, in simple terms; a painkiller. So hopefully, Raph should feel much better when he comes around from it."

"Sooo..." Mikey concluded in slow-motion, as his brain was trying to filter out all the fancy words and translate Donnie's sentence into a more understandable Mikey-lingual tongue. "Wait... Does that mean that you actually tried to _help_ him? Like, be nice to him?"

Donnie didn't answer. Instead, he momentarily looked up from his work, gave his youngest brother a crooked smile, and then went back to add a green liquid to a beaker with an orange substance. "Assuming there won't be any complications, of course. Most kinds of anesthesia have various undesirable side-effects, and I'm not entirely sure which one I just gave him."

Donnie picked up the canister again and squinted at the tiny text. "I'm fairly certain what its properties are, but not what it's called. I have to admit my shortcomings when it comes to the Russian language… Plus, drugs and medicines tend to have different names depending on where they are manufactured."

"You speak Russian…?" Mikey asked wide eyed.

"If I did, I'd know what I just gave Raph," Donnie stated, and put the canister away. "Like I said: please keep an eye on him for me."

Leo was only half aware of the conversation taking place. He was experiencing problems of his own, and his hazy head found it difficult to concentrate on all the words flying around above him. He had attempted to free his hand again, but felt like it was getting harder every time he tried. He had ignored it at first, but the truth was becoming painfully clear to him. He was getting weaker. Tired. He felt like he hadn't had water for days, and his muscles hurt as if he had just finished a brutal training session. Which was a very unnerving feeling when he in fact hadn't moved for what felt like hours. He had also recently noticed a gnawing pain in his head that wouldn't go away. He had tried to shake it off, but it got worse every time he moved.

"Are you okay over there, bro?"

Leo flinched at the sound of Mikey's voice, surprised to find that he wasn't talking to Donnie anymore. His bright blue eyes were observing Leo with concern written in them, apparently able to tell that Leo wasn't feeling well.

"I..." Leo started uncertainly. He didn't want to worry his brother, but didn't want to lie to him either. He looked up at the ceiling with a sigh, avoiding eye-contact. "It's okay Mikey. I'm... I'm just a little tired. It makes my head hurt. Don't worry about it."

"You sure?" Mike wondered, and twisted his head in a bird-like manner, as if looking at his brother from another angle would make his statement more convincing. "'Cause, you kinda look like you're gonna be sick. Are you?"

"... Don't worry about it," Leo repeated in a low voice. He didn't possess the energy to come up with a better answer. He hadn't lied to Mikey about his condition, but he hadn't told him the whole truth either. It was a fair compromise, and hopefully, Mikey would settle for this explanation. Like he had done before when Donnie was filling up all those vials with Leo's blood. It felt like a lifetime ago...

Leo took a deep breath and closed his eyes, trying to gain some control over his body. Slow, deep breaths. He wasn't going to allow himself to feel lightheaded. Wasn't going to allow his muscles to ache or his head to hurt. He needed them. He and his brothers were going to get out of here, and he needed his body for that to work. Slow deep breaths. Ignore that feeling of weightlessness, ignore the black spots dancing in front of him, ignore...

The sudden feeling of peacefulness was unexpected but welcomed. It felt like he had been transported to a higher plane where the maladies of his body were completely non-existent. He didn't know how it had happened. Didn't know if he was dead or alive anymore. But he wanted to stay like this. Could he do that? Was he allowed? He hoped so. He didn't think anyone would mind. At least for a while...

His reverie was cruelly interrupted by a piercing bright light, quickly followed by pain, nausea, and coldness rushing back to him. Overwhelming his senses. Leo tried to close his eyes again to get away from the intrusive brightness. He wanted to go back to the soft darkness, but something was keeping his eyelid open. Forcing him to look at the light that was moving in and out of focus. He didn't like it. The beam felt as sharp as a needle, and the eerie similarity made his heart beat faster in stress.

"Let go of me," Leo groaned feebly, trying to turn away his head. He winced when the sudden movement was rewarded with another spike of pain in his head.

"... He's back," Donnie declared. He finally removed the penlight from his brother's temporarily blinded eye, making Leo blink hard a couple of times to regain his vision.

"Leo!" he heard Mikey cheering from somewhere in the sidelines. "Man, you can't scare us like that, I thought you were gone! Like, _gone_ gone!"

"... W-what happened?" Leo wondered, feeling how his lucidity was returning to him. He hadn't even noticed that he was missing it.

"I would also like to know that," Donnie replied, and pried apart Leo's other eye to expose it to the penlight too, despite Leo's protests. "Mikey told me that you had stopped moving, and when I tried to rouse you, you were completely unresponsive. I think you must have blacked out, but I'm not sure why."

"You wouldn't talk to me, or look at me, or do anything!" Mikey clarified, still distressed by the memory. "It was scary, dude… Like in one of those zombie movies. But without all the blood, missing toes, and the bad teeth, and… Okay, you didn't really look like a zombie at all, but definitely something zombie-ish!"

"Are you feeling alright, Leo?" Donnie asked him, finally leaving his brother's eyes alone to meet them with a concerned expression. Leo observed the scientist with a wary look, not feeling too enthusiastic about sharing his medical state with the very person who was responsible for it in the first place.

"I didn't black out," he claimed. "I... tried to sleep a little. That's all. I promise, I feel fine..."

"You're not fine!" Mikey objected, with an upset look at the leader. Leo flinched at his exclamation, surprised to find the freckled turtle siding with the taller brother.

"Mikey..." Leo said in a low voice, giving the turtle an insistent look to tell him to stay quiet. But Mikey didn't share Leo's ambition to keep his condition a secret.

"He said that he was tired and that his head hurt," Mikey revealed to Donnie, with a determined look.

"He's been experiencing fatigue and headaches?" Donnie repeated in medical terms, scratching his head in confusion over this information. Mikey nodded with an important expression, while Leo made a deep sigh. Donnie then swiftly left them to free Raph from the analyzing cuff, and Leo could tell that the tool was about to switch owner again.

The blue masked turtle gave Mikey an annoyed look for the betrayal, but soon dropped it when he saw his brother's worried features. The older turtle's expression softened in sympathy. Mikey must have figured that the thought of Leo getting sicker was worse than the thought of what Donnie would do about it. And Leo couldn't blame him. Raph was out cold, and Leo was in a pretty bad shape too. If things would go south, there was a real possibility that the youngest turtle would be left all alone in this nightmare. He must have been genuinely terrified when Leo didn't want to wake up earlier. It was no wonder he had alerted Donnie...

Donnie strapped the cuff on to Leo's arm again, and then quickly left his side to check his vitals on the computer. He studied the results closely, his pupils darting from left to right.

"... Strange," he suddenly spoke up, presumably double checking the data to make sure that he wasn't incorrect. "Your blood pressure and vital signs haven't gone back to normal yet."

"And what does that mean?" Leo asked, surprised over how little he cared about the answer.

"Actually, it doesn't have to mean anything," Donnie elaborated with a shrug, leaning forward over the desk with his chin resting on his knuckles. "Your wristband isn't exactly 'cutting edge' in the heart monitor business. It basically uses light to shine through the skin and into the blood vessels to detect any changes in blood volume. I can see at least two problems with that in your case..."

He turned to Leo as if he expected his brother to agree with him, but a quick scan of Leo's face informed him that he had no idea of what the scientist was referring to. Donnie made a bored exhale at this and let his chair twirl around so he could face his brother properly.

"Our _skin_ is tougher than that of regular humans, and your _blood volume_ isn't back to normal levels," he explained with emphasizing hand gestures, before he turned back to the computer to write something down. "It's possible that those components mess with the analyzer somehow. _But,_ I'd also like to stress that these results are expected giving your current health, so I have no reason to doubt the instrument's reliability in this case."

"I don't _care_ what your computer is telling you," Leo argued impatiently. "I'm feeling better now, and I have no intention of ever blacking out again. Can't we just leave it at that?"

"Do you know what I'm looking at right now?" Donnie asked him calmly, keeping his eyes strictly focused on the screen without giving Leo as much as a glance.

"... No?"

"80 over 20," Donnie revealed simply. The statement was followed by a thick silence, where Leo patiently waited for his brother to continue, but where Donnie seemed to feel no obligation to explain himself further.

"What is that?" Leo finally asked, finding Donnie's lack of conversation unnerving.

"Hypotension," Donnie informed, finally turning away from the computer with a serious look at Leo. "Your blood pressure is abnormally low. I could prove it to you by removing your restraints and let you sit up, since a sudden change of position could literally make you faint in this condition, but I don't wanna add concussion to your symptoms as well."

"Try. I'll risk it," Leo claimed, with confidence.

"Yeah, that's what concerns me..." Donnie clarified tiredly, and started drumming his fingertips on the keyboard in a busy manner. "Anyway, the fact that your readings have stayed the same means that your recovery is taking more time than I anticipated, probably due to some sort of underlying complication... But you shouldn't be in any immediate danger as long none of these numbers reach critical levels and your only symptoms are weariness and a headache."

Donnie momentarily stopped tapping the keyboard, and turned to Leo with a slightly raised eyebrow. "Unless there's something of medical significance that you're not telling me about?"

The short answer was: Definitely. But Leo didn't feel like enlightening his brother about it. He didn't trust him with the information. This Donnie had a spooky habit of justifying the most disturbing ideas by stating that it was all for the sake of finding a retro-mutagen. For science. It was disheartening to see Donatello, the most ethical person Leo knew, go through with these things without even hesitating. And what worried him the most was the fact that despite all the things Donnie had done to his brothers, he still claimed to care about them. That he didn't want them to get badly hurt. Some would say it was a reassuring thing. That it proved that the real Donatello was still in there somewhere. But Leo thought this made Donnie even more dangerous. It was difficult to be on your toes around someone who talked and acted so much like their harmless, lovable brother. Right up to the moment he no longer was.

Donnie apparently interpreted Leo's silence as an inconclusive answer, and left his chair to take a closer look at his specimen. Leo could almost feel how his brother's calculating eyes were moving all over his body. Studying every twitching muscle, breath, or even eye-movement in order to diagnose him. Leo swallowed involuntary, feeling as if he was on display in front of a jury that was grading his performance as a healthy individual. He closed his eyes and tried to pay as little attention as possible to Donnie's hands that snaked over his skin. Feeling for a pulse on his neck, resting on his forehead to check his temperature, and pinching his fingertips for a medical reason Leo couldn't figure out. Leo tried not think of how intrusive the procedure felt, and was so occupied with blocking out Donnie's presence that he at first didn't notice how his right arm was released from the restraints.

He blinked in shock when he felt how the belts slipped off his wrist, and quickly turned his head to make sure that he wasn't imagining it. Donnie was standing right next to Leo's freed arm, looking down at him. He then made an inviting gesture towards himself.

"Hit me," Donnie instructed him.

He was kidding. He had to be. There was no way he could be serious. But even with his arm untied, Leo still hesitated. His upper and lower body was still firmly secured. There was no way for him to leave the table unless he could undo another seat-belt, and Donnie would most likely stop him the second he tried. But not if Leo knocked him out first. He could easily reach him from this position.

But it couldn't be this simple, could it?

Leo ignored the last thought. He gathered up all the energy he had left and took a swing at the scientist, aiming for a pressure point on the arm to maximize the damage. The punch hit Donnie on the left side of his plastron. It wasn't a pressure point, and the force was nowhere near enough to bring down the turtle, or even make him wince.

"Hmm… Okay," Donnie pondered, with a thoughtful expression at his own chest, but then looked at Leo while tapping the area in an encouraging way. "Can you hit the same place again?"

Leo didn't like the idea of taking directions from Donnie, but he couldn't give up the plan just for the sake of rebelling against him. That was more Raph's thing. Leo decided to try again, concentrating and bringing all he got into the attack. But the result was the same, with the only difference that his fist ended up on the other side of the plastron this time. The hit was so weak that it could have been mistaken for an attempt to wipe off some smudge from Donnie's chest.

The scientist was still standing patiently by Leo's side, politely waiting for him to give it another try. When Leo did no such thing, Donnie made a sigh and picked up the seat belts. Leo tried to retrieve his arm before Donnie could strap it to the table, but he didn't have enough energy left to put up a fight. The leader started to feel nauseous when Donnie pinned down the arm to secure it again. Taking away his brief moment of freedom.

"Dude, what kind of punch was that?" Mikey asked Leo straight out, with a puzzled frown. "I think I've seen Spike eat salad with more attitude than that. What gives?"

"I can tell you that," Donnie said in Leo's place, as he made sure the belts were tight enough. "Except from the fatigue and headaches you told me about, Leo suffers from dizziness, volumetric thirst, muscle cramps, and most likely perceived muscle weakness." He looked up and turned to Leo with a curious look. "Feel free to stop me if I get any of this wrong."

Leo didn't. The scientist was spot on with everything, and it felt silly to try and hide it anymore. The only thing he could do now was to hope that Donnie wouldn't act on this new intel. So far, most of Donnie's treatments seemed to be more excruciating than whatever they were supposed to treat.

"You could tell all that stuff from just letting him _hit_ you?" Mikey wondered, looking almost fascinated by the thought.

"More or less. It's not an absolute accuracy, but I had to figure it out somehow since he didn't wanna tell me..." Donnie clarified. He straightened up from his hunched position with a look at the blue masked turtle. "You're basically experiencing symptoms from your excessive blood loss, possibly even hyponatremia if your sodium levels are too low, but I can't tell for sure without another blood-test... Oh, but don't worry, I'm not gonna take any more blood from you." He made an apologetic chuckle as he reassuringly patted Leo's needle-pricked arm, making the turtle flinch in pain.

"But if I'm right," he continued, as he walked back to his desk. "the headache and muscle pain can get pretty bad if left untreated. Now, the standing procedure would be to give the patient intravenous fluid replacement. But if you happen to live in a sewer with limited access to hospital equipment, I guess an oral rehydration solution will have to do instead… I'm pretty sure I got everything I need right here in the lab. I just have to add the right proportions of electrolytes to the mix and you'll be all better."

"I don't think..." Leo tried to object, but the scientist had already put himself to work. He was carefully measuring different kinds of powders and liquids, only to merrily stir them down into a big glass container in the same spirit as if he was in a cook-off. Leo didn't have a clear view of what was added to the content, but he doubted he would understand what most of it was. Though, he was certain that he at one point saw the turtle pour down something that looked a lot like salt or sugar. Whatever the components were, it gave the mixture a pale, almost foggy look. Like water diluted with milk.

"It's okay, bro," Mikey told Leo reassuringly. "I've read enough comic books to know that the bad kind of stuff is supposed to be green. Or red. Sometimes purple, but that's like ridiculously super-rare. I think I've only seen it once in a- "

He stopped himself when he caught a glance of Leo's face. His brother was barely keeping his eyes open, and his manner was a bit distant compared to before, as if he was only half aware of the freckled turtle's loud voice. Mikey raised his eyebrow slightly. "Dude, are you hearing any of this?"

Leo let out a weary sigh and shook his head with a miserable expression. Mikey gave him a peculiar look before leaning closer, lowering his voice to a whisper. "Do you want me to stop talking for a while?"

"Would you…?" Leo asked with an almost begging look, knowing that it wasn't an easy request to ask from Mikey. But the freckled turtle just smiled at him and made a motion where he pretended to zip his mouth. The action came out clumsy, since his tied up hands didn't allow him to use any refined gestures. Leo gave him a small appreciative smile, but dropped it when he saw Donnie finishing up at the desk. He poured some of the mixture in a small beaker with a wide bottom and a narrow neck. He then picked it up and swirled the liquid in his hands before going back to Leo with it.

"What exactly is that?" Leo felt the need to ask, strongly suspecting that he was going to regret the question.

"As I'm pretty sure I explained to you approximately six minutes ago;" Donnie politely explained, and tapped a finger on the glass-container in his hand. "it's a type of homemade fluid replacement. It mainly contains the water-solvable electrolytes that you're running low on for the moment, like potassium chloride, glucose, and sodium. In very precise proportions, if I might add."

"… are you gonna make me drink it?" Leo wondered, with just enough hostility to show what he thought about the idea.

"I don't see why I would have to 'make' you drink this," Donnie replied with a frown, genuinely confused by Leo's comment. "Your body is suffering from various kinds of deficiencies, and it looks like you're not gonna get better any time soon unless we ease the symptoms. Do you wanna get better? Because if you don't, I can see how drinking this would totally foil your plan to lose basic motor functions, perception, and experience increasing pain in your extremities."

Leo looked at the container with wary eyes. The idea of drinking something Donnie had prepared wasn't an appealing thought, not even during normal circumstances. There was a reason why Mikey was their designated cook... But it really looked like Donnie wasn't trying to force him to do it. Leo still didn't feel very well... If he got an opportunity to escape, he was more likely to end up collapsed on the floor than outside the lab. Neither his mind nor body was working the way they should right now. Donnie had even freed Leo's arm, and he couldn't even use it to punch him properly. He couldn't save anyone like this. He couldn't save Raph and Mikey…

He had no choice. If he and his brothers would have a fighting chance at freedom, he needed to speed up his recovery. Even if it meant playing along with Donnie's delusions. Leo finally gave the tall turtle a defeated nod, silently giving him permission to execute the treatment. Donnie leaned closer over him and let the beaker rest at Leo's mouth, carefully tilting it to let a small stream of liquid pour out and touch his tongue.

Leo violently flinched away from the glass-container the very moment he felt the vile taste hit him, unable to swallow more than a spoon of the stuff. Donnie only narrowly managed to retrieve the beaker in time to save its content from spilling.

"Whoa! Careful, Leo. Just try to take small sips," Donnie suggested calmly.

"Don't worry," Leo panted, with a rueful grimace. "it isn't as appetizing as you think..."

"I didn't expect it to be," Donnie explained, and dipped his finger in the pale water and put it in his mouth, tasting the content with a pondering look. "This solution contains saline. Rough translation; liquid table salt, which coincidentally is a common solution used to induce vomiting in cases of severe intoxica- ...Sorry, that wasn't very helpful. Forget what I said. Um… Try again?"

Leo took a deep breath, trying to mentally detach himself from his tongue in order to ignore the lingering taste. He then reluctantly opened his mouth slightly. Donnie smiled a little, and made the glass touch Leo's lips again to let the ghost-white fluid pour into his mouth. Leo tried to swallow as much of it as he could, but the simple task proved to be much harder than he thought. The taste was absolutely horrible. Like a bitter mix of seawater and a pinch of something sweet. Flavors never meant to share a confined space together. Leo could feel how his gag reflex protested with each gulp he convinced himself to take. It was like his whole body was rejecting the medicine, like a fortress refusing to let in a suspicious intruder.

Leo soon had to close his lips again and shook his head until Donnie removed the mixture from him. "... Stop! Just... Stop it."

"It's alright, just a little more," Donnie coaxed, and made a motion to continue administering the liquid.

"No, no I don't want anymore," Leo protested, turning his head away to avoid Donnie's hand.

"Come on Leo, don't be like that. Look, it can't be more than one third left. That's like one third away from nothing," Donnie urged in a comforting voice, and nudged the corner of Leo's mouth with the beaker. "Just open your mouth again."

"I _can't._ Stop that..." Leo insisted angrily, with a stern look at his brother. "I've changed my mind, okay? I've managed to drink some of it, that's gotta be enough..."

"It doesn't work like that," Donnie pointed out, with a subtle head-shake. "There are no shortcuts in modern medicine. You can't just settle with consuming _some_ of the solution and expect that it's gonna help you the same way. You really have to finish the whole thing if you want it to have any effect on you at all."

"And a half dose is better than nothing. I'm sure I can manage," Leo claimed, trying to sound determined enough to end the discussion.

But Donnie didn't put away the glass container. He dropped his head in mild annoyance before giving Leo a look. "Okay, take this from someone who has a _way_ wider perspective of what happens to your body when suffering from low blood volume; if you don't finish this mixture, you'll most likely be very sorry you didn't later. You think you're feeling sick right now, but the fact is that you're only displaying a handful of all the symptoms associated with your condition. This is gonna get worse before it gets better, and I think you know exactly what I mean by that."

Leo hesitated, carefully considering Donnie's words in his head. He hated how rational he sounded. If Donnie wasn't making any sense, it would be much easier to reject his reason. He didn't want the scientist to be right. And he didn't want to continue drinking this vomit-inducing remedy. But he knew that Donnie was right. And if Leo would have any realistic chance of regaining enough strength to escape, there was only one thing he could do.

Donnie offered him the glass again. The leader swallowed uncomfortably at the sight of it, but didn't turn away when the scientist started pouring the sickly pale liquid through Leo's slightly parted lips. He closed his eyes with a faint hope that it wouldn't be so bad this time. But the taste was still nauseating, and he could feel himself gagging as he tried to swallow as much as possible in an attempt to get rid of it faster. It was a battle between mind and body, where his brain kept telling him how important it was to drink the solution and his stomach insisted that this poison had no business inside Leo's intestines. The brain's argument felt less compelling by every second.

The blue clad turtle couldn't take it anymore. He turned away from the glass container, refusing to continue the procedure. But he was only allowed a moment of relief. His eyes widened when he suddenly felt a pair of fingers pinching his nose, and how the beaker was pushed inside his unexpected mouth. He cringed when he felt the disgusting liquid entering him again. He desperately tried to shake off the intrusive hand and container, but it was no use. Donnie was perfectly able to cut off his air supply and hold his head still while feeding him the rest of the concoction. There wasn't anything Leo could do but to keep gulping down the vile water against his will. Quietly hoping that Donnie wasn't gonna let him drown from it. He wondered how Raph must have felt down in the water tank…

Donnie suddenly removed the glass from Leo's mouth and the fingers from his nose, allowing him to breathe again. Leo was gasping and coughing sickly, as if he had been washed up on a beach after a storm.

"Don- _cough-_ Donnie, please stop..." Leo managed to choke out weakly, feeling his insides turning from the experience. His throat felt too sore to talk, but he had to do something to stop the scientist from making him drink the liquid again. He had to tell him, even if he wouldn't listen. "I can't- _cough_- I can't do this. Okay? This stuff is not staying down, I can feel- _cough_ ... Please, I think it's gonna come up again..."

"It's okay, it's okay, Leo. Don't worry about it, bro," Donnie said, and patted Leo's chest reassuringly. He then made a presenting motion to the beaker in his hand. "There's nothing left now. See? You finished the whole thing. Just lie still for a while and let your body digest it, alright? You'll feel better soon, I promise."

Leo coughed again as he tried to get rid of the remaining taste in his throat and mouth. He turned to Donatello with a dark glare. "You said you wouldn't force me to drink it."

"And _you_ said you wanted to get better. Right?" Donnie replied simply, and gave Leo's shoulder a soft squeeze before he went back to his desk. "I did what you asked, not what I said. Funny how that turned out."

"How long will it take to work?" Leo wondered in a low voice, having second thoughts on his decision to go through with the treatment in the first place.

"Well, considering the amount of fluid loss in combination with how far progressed your symptoms are... " Donnie counted on his fingers and calculated something in his head before turning back to Leo with a comically blank face. "… I have no idea. You could feel better within a couple minutes, but it could just as well take an hour. Or two. We'll just have to wait and see."

Leo let his head fall back with a tired sigh, not happy with Donnie's idea of an answer. Donnie didn't take any notice of him, and instead picked up the egg-shaped timer and turned it up to an unknown amount of minutes.

"I'm just gonna make sure that Raph doesn't display any signs of allergies to the antibiotics," he shared openly, as he left the table and headed towards the red clad turtle. He met Leo's eye's briefly on the way and made a swift gesture to the desk behind him. "I set the timer for when your next dose is up. It seemed like a good idea; since we're gonna have to do this regularly until the bigger container is empty."

"Great..." Leo muttered without enthusiasm, and gave the timer a long uneasy look. He dearly hoped that Donnie hadn't set it too soon. He wasn't planning on being around when the alarm went off.

"… Is it okay if I go back to talking now?" Mikey's soft voice suddenly spoke up next to him. "I think you look a little better?"

He knew that Mikey was lying, because he felt more nauseous than ever. He could almost physically feel how the color was being drained from his face, and he was certain that a sudden movement would make him throw up for sure. He took another deep breath, ignoring his aching body so he could make his voice as steady as possible. "Mikey... If you and Raph get any chance to escape... You have to promise me that you'll leave m-"

"NOT LISTENING!" Mikey cried out so suddenly that Leo's eyes took the size of baseballs before he turned to his younger brother with a frown. Mikey was spinning his chair again with his eyes stubbornly closed. "Nope! No, no, can't hear ya'. La la la la, _crazy_ noises over here, la la la la..."

"I'm serious, stop joking..." Leo told him, with a hint of irritation.

"I'm not joking, _you're_ joking," Mikey claimed, and shot Leo a judging glare every time the revolving chair let their eyes meet. "'Cause you can't be serious if you're trying to say what I think you're trying to say, and if you are saying that, then don't you dare say what I think- … You get my point!"

"… No, I think you lost me."

"_You_ said that we're gonna get out of here together, remember?" Mikey elaborated, as the chair finally slowed down enough for them to have the conversation face to face. "That's Raph, you, and me. _That's_ the plan, and it's a _great_ plan. We just have to make it happen. Don't start making up some lame plan B that one of us isn't part of. What kind of plan is that? No turtle left behind, right? Raph says that's a rule, so you better not break it, or he might break your leg or something... I don't know. I'd rather just not break it if I were you."

Leo surprised himself when he suddenly started to laugh at Mikey's improvised pep-talk. Mikey had always had a strange gift of cheering up or annoy his surroundings, and Leo almost envied how it came so natural to him even in the worst kinds of scenarios.

"Fine. It's a deal." Leo smiled, and gave his brother a determined look. "If we escape, we escape together. And that's a promise."

"Seems like a rather odd arrangement considering that you're not prisoners and are free to leave whenever you want," Donnie suddenly added, from where he was examining Raphael. Both Leo and Mikey stared at him in utter disbelief. Not because of the fact that he apparently had been aware of their conversation, but mostly because of what he just had told them.

"What did you just say…?" Leo asked him, but the words were so clear in his head that he knew he couldn't have misheard them. "So... if I would ask you to cut me lose right now...?"

"I wouldn't," Donnie stated simply, while forcing Raph's jaws apart to check his tongue.

"That's funny, because I thought you just said-" Leo began tetchily, but was quickly interrupted.

"I _know_ what I just said," Donnie explained tiredly as he quickly finished up his work on Raph, and headed back to his desk. "But right now, you're all playing a crucial part in my research, and it would spoil hours of work to have you all walk out in the middle of it like this. But don't sweat it. The moment I'm done, you can do whatever you feel like and ignore me like you usually do."

"And when will you be done?" Leo asked warily, not allowing himself to get his hopes up.

"I'll let you know," Donnie revealed casually, as he brought back his container with attempted retro-mutagen along with some vials of mutated turtle blood to test it on.

"Seriously?" Leo groaned in frustration. "Come on, Don. You've been at this for almost a full day already. Don't you think it's time for a break? You said that you barely slept at all last night. How are you supposed to focus on your work if you're sleep deprived?"

"Don't worry, I have means of making myself stay alert," Donnie assured him with a semi-smile, and patted the right pocket on his lab coat. Leo had no idea what he meant by it, and the scientist went back to his lab equipment without explaining it further.

"And by the way, I can't go to sleep yet," Donnie continued, his face suddenly furrowed in concentration as he was adding a blue liquid to the container. "I still got tons of stuff I need to do today, _and_ tons of stuff I should have done before that. I can't rest when I'm at the peak of solving something I feared was unsolvable. This is too important for that. But I guess you wouldn't understand..."

"We get it," Leo clarified, with a firm look at his brother. "We understand that finding a retro-mutagen is a top priority, but that doesn't mean that you have to spend every waking hour doing it!"

"Then you _don't_ get it," Donnie stated, with such dark look at his brothers that Leo almost got the impression that he had insulted him. The scientist reached for his bō staff and hit a poster about turtle anatomy on the wall behind him, like a pointer at a world map. His voice was about as calm and composed as the eye of a storm; a false sense of security.

"What I'm essentially trying to do here is to find a way to turn people that's been mutated by the Kraang back to normal. Are you with me?" he rapidly explained, and frenetically tapped a certain spot on the poster which Leo couldn't quite see from his angle. "But we're not talking about a couple of single based nucleotides that's been misplaced here and there, oh, no, no, we are talking about a chemical agent that _completely_ reverse engineer the victim into something that's as _far_ _away_ from its original genetic makeup it can possibly be!"

Donnie had suddenly extended the naginata blade and without warning sliced the poster to shreds. Causing Mikey to jump at the sudden action and Leo to stare at him in shock. The tiny pieces were swirling around the scientist's serious face and settled down like big snowflakes in his surroundings. Or like ashes from a recently erupted volcano.

"That's not an easy fix," he concluded with a grim look at his brothers. "It's comparable to finding a cure for cancer."

Neither Mikey nor Leo could figure out how to respond to this statement, but Donnie didn't wait for one. He simply put away his staff and went back to fiddling with some glass-slides, apparently ready to test a new batch of attempted retro-mutagen. He peeked through the microscope and studied a sample with interest, but then made a frustrated face-palm. Apparently not getting the result he was hoping for.

"... Donnie," Leo started with a sincere look. "Despite what you might think, I _can_ empathize with your situation. I know what it's like… You're not the only one with a responsibility. To have people looking to you for all the answers. To fear that you'll let them down. You're _not_ alone. But you're literary losing yourself in this work, and you've completely lost sight of the things you used to value and care about…! Can't you see that?"

Leo paused to see if his words were reaching Donnie. The scientist was once again busy with adding new components to his experiment, and his face was so focused on the task that it was hard to tell if he had been listening at all.

"Please Donnie, just... Just _try_ to think about what you're doing, okay?" Leo asked him, with an insistent look. "I'm not telling you to stop. I'm just asking you to allow yourself to have second thoughts on what's going on here. Think of what you're doing to us, your brothers, think about Mater Splinter-"

"Think about April!" Mikey suggested out of nowhere. His comment was followed by a brief period of silence where Leo stared at Mikey and the younger turtle responded with a clueless shrug.

"... April?" Donnie's voice was close to inaudible. He slowly looked up from his experiment with a blank expression, as if he suddenly had lost interest in it. Mikey looked genuinely surprised over Donnie's reaction, but Leo turned to the freckled turtle with an encouraging smile. He wanted to slap himself for not thinking about this earlier.

"Yes! April," Leo continued in Mikey's place. "Take a look at yourself, Donatello. You're acting like a crazy scientist, and the Donnie she knows is far from one. He's the guy who helps her with her homework, who practices ninjutsu with her, gives her all of his pizza gyoza-"

"Even when he wanna eat them himself," Mikey eagerly added, feeling that the last detail was of great importance.

"The Donnie she knows would never do something like this," Leo continued, with great conviction. "And I think that deep inside, you know that just as well as we do."

"... I can't do this to her," Donnie answered after a moment, and turned away from his desk with a light head-shake.

"Kinda hurtful that he cares more about a girl than his own brothers..." Mikey pointed out, with a raised eyebrow at the purple clad turtle.

"I'm perfectly happy with being second to April as long as his feelings for her can make him go back to normal," Leo told him in his most rational voice, not looking the least bit bothered by Mikey's observation.

"Actually," Donnie soon added, and held up a finger in a correcting gesture. "I was thinking more of the fact that since she's neither a mutant, nor susceptible to the mutation process, these kinds of experiments would be a waste of time and resources on her."

"… Oh," Leo said, and shared a surprised look with Mikey over the unexpected statement.

"However," Donnie elaborated, and got up from his chair with a curious look on his face. "I would like to study where she got those anti-mutagen properties from. Huh. I can't believe that I've never looked into it before. This could really help me in my research. Maybe if..."

Donnie stopped for a moment and rested his chin on his fist in a contemplative manner. He let his eyes wander freely all over the place as if he was thinking hard on something. Mikey and Leo blinked in confusion at the scene in front of them. It was strange to see Donnie just standing there, doing absolutely nothing.

"What are you thinking?" Leo finally asked, finding the silence uncomfortable.

"I'm evaluating whether exsanguination is an acceptable risk for a decent amount of samples from her," he revealed in a pondering way. But after a few seconds, he made a nod and picked up his T-phone from his pocket. "Hey, April! What's up?"

"Um, dude…?" Mikey asked Leo with a weird look, as he watched Donnie leave the area in order to talk with his lady-friend in private. "What's an ex-invitation or whatever?"

"Something the Donnie we know would rather cut of his own arm than do to April," was Leo's answer, as he watched in horror how Donnie headed for the exit. He was still talking to April, very much in the same awkward manner he usually did, as he shut the lab door behind him.

"... He's gonna ask her to come down here," Leo realized, staring at the door as if it was a monster that was ready to claim its next victim.

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><p><strong>Next Time<strong>: Getting close to the end! The brothers can't let Donnie hurt April, and decides to break free before it comes to that. Mikey has a surprise, but so does Donnie…


	7. Chapter 6: Take a deep breath

**Author's Note:** This was a heavy chapter to write, and I'm sorry if I've kept you waiting. ó.ò As you might remember, chapter 5 turned out too long and I had to cut it short. Well, turns out that the problem still remains. ^^; And what's even worse: I've come to the horrible realization that I must completely remove an upcoming plot point. Chapter 7 is the climax of the story, and if I don't remove this part, it would be pushed on to chapter 8. It's sad, since this was actually based on an idea from one of you readers that I really, really liked and wanted to include. However, I'm planning on adding it as perhaps a bonus chapter in the end. A kind of chapter 6.5. ^-^

This buddy took a long time to write, but I hope you'll like it. :) Any grammatical errors or funny-looking language should be reported directly to me! ;D

* * *

><p><strong>Chapter 6: "Take a deep breath"<strong>

"Relax, bro... Donnie would never do anything to April," Mikey stated, and gave Leo a reassuring smile, feeling that it was his duty as little brother to cheer him up. "He likes her too much. It's the same with me and cupcakes. Some of them are just too cute to eat, you know? They're like muffins with party hats."

"It's not that simple, Mikey. Look at what 'Donnie' has done to us so far," Leo pointed out, with a nod to the restraints and the scribbles on his plastron. He could only just read the words "incision here" right next to a crude drawing of his own heart. "It doesn't matter how much he likes her. He'll end up hurting her anyway."

"…Dude. _Exactly_ like me and cupcakes."

"We don't have much time," Leo continued, with a worried look at the doors. "We can't let him do this to April… Is there anything we haven't tried yet? And I mean _anything_-"

"… He asked you to _hit_ _him_."

Leo blinked in surprise and turned his head to the red clad turtle on the cot. Raph looked up slightly from the bed, only to shoot the leader a glare. He didn't look the least bit tired anymore.

"Raph!" Mikey cheered in excitement, as if he'd just found out that his birthday had been moved to tomorrow.

"But when did you-" Leo started, but then seemed to realize something. He glanced at Raph with an uncertain look. "… How long have you been awake?"

"Long enough to know that you had the chance to give that maniac another gap in his teeth, and yet we're still here!" Raph shared, looking furious. "What the heck was that about?!"

Leo sighed in reply, having a feeling that Raph was never going to let him live this one down. Truth be told, Leo wasn't sure if he would ever let _himself_ live this down. That moment, that _opportunity_… It hadn't just been embarrassing; it had felt like he was letting everyone down. Again.

"Seriously, what's wrong with you?" Raph asked, growing tired of the silence. When Leo didn't answer this time either, Raph's angry look changed into a surprised one. "… What did he do to you?"

"We're running out of time," Leo replied instead, and gave Raph a look. "I assume that you also heard the part where Donnie is gonna bring April here? And it didn't exactly sound like a date."

Raph stared at Leo in horror and immediately started tugging at his restraints, as if he thought he'd be more successful if the belts weren't prepared for an attack. Raph closed his eyes while trying to break the bonds, and couldn't see how the belts were digging into his flesh. He gritted his teeth in pain and let out a frustrated growl before his shoulders suddenly slumped and his head dropped to the mattress. He sighed in utter exhaustion and gave Leo a look. "Alright, you're the boss. What's the plan this time?"

"Don't worry," Leo answered, with the confident smile of a certain spaceship captain. "I've got a really good one. Soon, I hope…"

"So… you're plan is to _plan_ to have a plan?"

"… A little bit like that, yeah."

"That's a _great_ plan!" Raph exclaimed, with a level of sarcasm that even a deaf person could hear.

"Hey, wanna hear my plan?" Mikey asked cheerfully, before lowering his voice in a scheming manner. "All we have to do is to find Donnie's weakness... Trust me. I've played _a lot_ of video games. Once you find the weak spot, the boss gets _really_ super easy to beat."

"Mikey, we've been over this. Real life is not a video-"

"Donnie's weakness is candy," Mikey continued stubbornly. "It has to be, right? He's eating lollipops, like, _all the time_. Man… It's scary when people get addicted to food like that."

"Once we're free, I'll hook you both up with a nice treatment program," Raph promised, and turned to Leo with a frown. "But seriously, when did Donnie get such a sweet tooth?"

"I don't know," Leo replied, and shook his head. "But I'm betting it has something to do with him not feeling the need to sleep. Maybe he's taking something to keep himself going...?"

"Whatever it is, he'll probably shove it down our throats if we ask about it. You know, just to be nice," Raph said sarcastically and started to violently pull at the belts. "And I'm _not_ sticking around for that!"

"Dude, you've tried that like eighteen times already," Mikey pointed out, with a bored look.

"Nineteenth time's the charm…!" Raph growled in response.

"Hey, Mikey. You managed to knock over those glass containers before, remember?" Leo asked his little brother.

"Geez… First Donnie's busting my shell for that and now you?" Mikey groaned. "I'll pay for them, okay? Or glue them… I'm a little low on cash."

"Can you reach anything else from your chair?" Leo asked, with a serious look.

"Oh. Um… Give me a sec." Mikey made the chair spin slowly and analyzed his surroundings. "Uh… The corner of the small table, I think… And maaaybe Raph's bed if I stretch my leg. Wait, I'll check."

Mikey started to squirm in his seat. The cord loosened around his body and allowed him to almost slip completely out of the chair. His feet could now easily touch the floor and he tried to reach for Raph's bed with his toes. He managed to nudge it just barely. Leo stared at him.

"Mikey, you… You can move!" Leo called out, with a look of disbelief at his little brother.

"Huh? Oh, yeah," Mikey confirmed, and sat up straight again. "This cable cord is pretty loose. Like a strawberry twizzler or something. What? Are your ropes not like that?"

"How did you do it? You could barely even twitch when Donnie took that blood sample from you earlier!" Leo wanted to know.

"Easy, bro," Mikey said, with a smile. "You just turn your chair to the left, and then right, and- Wait… I think it was the other way around… I'll get back to you when I've figured it out."

"He's been free _the whole time_…?" Raph asked, and stared at Mikey as if he couldn't decide whether to give him a pat on the shoulder or punch him in the face. "_You've got to be kidding me…!"_

"Let's hope he isn't," Leo pointed out, and turned to the youngest turtle. "Mikey, how much can you move?"

Mikey immediately started to wriggle his arms, but could only move them slightly to the right and left. "Um… Okay, maybe not as much as I thought. But I can still reach the floor with my feet, though!"

"Then use your feet and roll over to-" Raph began, but then noticed the lower part of the former revolving chair. He raised an eyebrow. "… Isn't that thing supposed to have wheels?"

"Long story," Leo told him, and then gave Mikey an encouraging look. "But this is great! Now we can-" Leo paused with a frown. "… Actually, I have no idea how we can use this to our advantage."

"What are you talking about? Mikey is almost free!" Raph said, but then blinked as if he just realized what he'd just said. He sighed bitterly. "Oh, right. I forgot. It's Mikey…"

"Hey! Just tell me what to do and I'll do it!" Mikey claimed, with a narrow look at his pessimistic siblings.

"I hate to say it, but Mikey is our best shot to get out of here," Leo admitted. "Not just because he's the only one who can move, but he's also the only one of us who would have a fighting chance against Donnie right now."

"Did Donnie switch your brains while I was sleep, 'cause you can't be serious!" Raph yelled, looking deeply offended. "I can take him out way faster than Mikey can! Have you ever seen Donnie win over me in a fight?"

"You've been drugged, injected with antibiotics, and you literally just woke up after being knocked out with anesthesia. How confident are you that you could beat Donnie in this state, _unarmed_?" Leo asked, with a stern look at Raph. "And did I mention the part where you almost drowned and were barely brought back to life!"

"Yeah, that was scary…" Mikey reminisced. "Donnie had to give you mouth to m-"

"Raph doesn't need to know that part, Mikey," Leo swiftly interrupted him.

"I can still take him on!" Raph claimed, with the stubbornness of someone who takes great pride in harming others. "Or what? Are you saying that you're in better shape than me?"

Leo shook his head. "I'm not… To be perfectly honest, I'm getting more and more certain that I'll end up in a heap on the floor if I try to stand up straight. I won't be a match for Donnie like this."

Raph watched Leo in silence for a second. "Okay, I'm gonna ask you again… What the _heck_ did he do to you?"

"Dr Donnie-stein took all of Leo's blood," Mikey informed him, with an important nod. "He went all out vampire on him, bro. The needle kind. Super-creepy..."

"But he has only taken one vial of blood from Mikey," Leo continued, trying to deflect the subject from of his current health. "One vial, and that's it. Believe it or not, but he's in the best fighting condition out of the three of us."

"I think I'm feeling nauseous again..." Raph muttered miserably.

"Tough it out."

"Don't worry brochachos. I'll save ya," Mikey said reassuringly, and started squirming in his seat again. "Just gimme a minute. I'm gonna get this thing off…"

"We might not have a minute," Leo stated, with a quick glance at the doors. "Plus, your wrists and ankles are still tied up. Even if you were free from the chair, you wouldn't be able to walk. Do you have a knife on you?"

Mikey answered Leo's inquiry with a grin. "Like a ninja do-" The freckled turtle stopped talking in the middle of the sentence with a sudden blank expression, like someone who's trying to remember if he left the stove on before going out. Mikey's expression soon changed into an annoyed one. "… Oh, nuts!"

"Mikey…!" Leo groaned in frustration.

"What? We're not on a mission, how was I supposed to know I'd need one!" Mikey said defensively.

"It's standard equipment!"

"Well, do you have a knife then?"

"I'm tied up!"

"Dude… That excuse is getting kinda old."

Leo closed his eyes and sighed. They had all the pieces to this puzzle, he was certain of it. But he had no idea of how to put them together in order to get the image they wanted. An image depicturing Raph, Mikey and himself safe outside the lab. And preferably with Donnie tied up in his own chair.

Leo's thoughts were interrupted by a strange thumping noise. Leo looked up only to find Raph determinedly kicking his left foot hard against his bed. Repeatedly. The two brothers stared at him in silence before Mikey turned to Leo with a low voice. "… You didn't hear this from me, but I think Raph's lost it. Gone loco, you know? Dropped the ping pong ball. Lost the ticket to the circus. Complete wacko-"

A sound of metal hitting the floor made Mikey shut up, and he snapped his head towards it. Raph had stopped the kicking and a small throwing knife was now lying underneath the red clad turtle's cot. He turned to Mikey with a serious look. "Can you reach that?"

"Like a rocket to the moon, bro!" Mikey happily announced, and immediately slithered down in his chair as much as possible. He then stretched out his legs as far as the restraints would allow him, trying to reach the tiny object. "… Come _on_, Stubby…! You can _do it_… I believe… in… _you_… Don't fail me now…"

Mikey touched the knife several times with his toes, but only managed to move it around on the floor. Leo cringed at the unsuccessful attempts and Raph simply shook his head. Mikey glared at the knife, as if it was doing this on purpose. Even though the tool didn't possess any facial expressions whatsoever, Mikey could swear that it was mocking him. It probably wouldn't mind watching him fail at this all day long. But they didn't have all day.

Mikey made a stabbing motion with his legs at the tiny object, like a cobra charging at a mouse. His eyes widened in surprise when he suddenly felt the cold metal between his toes, and he squeezed it hard to not lose it.

"Nicely done, Mikey!" Leo said in relief. "Now, cut yourself loose!"

"No problemo!" Mikey declared with a grin, and stretched out his tied hands towards the object. Mikey's grin was replaced with a frown as his arms were too short to reach his toes. Or possibly the other way around. "Um… Okay, some problemo. My hands are up here, and my feet are down there. And my knees only bend down, not up…"

"Maybe Donnie can help you with that?" Raph suggested, as a morbid reminder of the scientist's current state of mind.

"Just try to reach it anyway," Leo coaxed. "You're extremely flexible, Mikey. Like a… Like a super hero! Keep stretching your arms, I know you can get it!"

Mikey did as his older brother said and stretched his arms, while at the same time trying to bring his feet closer to his body. "Almost…! … No, not really. Hngh…"

"Come on, Mikey, come on…" Leo begged, with an anxious look. "We've wasted enough time already."

"I'm… _Trying_…!"

"Try faster!" Raph snapped. "What are you doing? Practicing yoga?"

"Fine! I'll throw it!"

"NO!" Leo yelled, but it was too late. Mikey used his legs to toss the knife up in the air in order to catch it with his hands. The throw was horribly miscalculated and the small weapon landed on the floor, way out of Mikey's reach. Mikey observed the lost weapon in a contemplative way.

"I got this, bros," Mikey assured them, with a determined look at the knife. "All we need is a string and a magnet. Do you guys have any?"

Leo turned away with an exasperated sigh and closed his eyes again. He wasn't angry with Raph for provoking Mikey. Or with Mikey, for literally throwing away their first real means of escape… But he was furious at himself. Leo wished that he could move his arms just so that he could slap himself hard in the face. He should have known better than to get his hopes up. To think for even a second that they could escape Donnie's lab.

Leo opened his eyes in confusion as the thumping sound started again. He looked at Raph. The red masked turtle had started kicking the bed with his other foot this time. And judging by his wincing face, Leo could tell that it was the same leg the antibiotic had been injected in earlier. Raph quickly stopped the kicking when another knife fell out and hit the floor. Leo stared at his brother. "How many of those things do you have?"

"How many do you need?" Raph answered indifferently.

"Never mind," Leo replied, with a cautious look at the turtle, before turning to the younger turtle. "Okay, Mikey. Just like the last time. But be _careful_. I don't care if Raph's got three or thirty knives hidden on him. We don't have time for this."

Mikey nodded with an uncharacteristically serious look and tried to reach the small piece of metal. It didn't take long for him to pick it up this time, and the freckled turtle studied the tiny weapon uncertainly. He then gave the knife a resolute glare. "I'm gonna try again…"

"_Don't_ try again! It's no use-"

But Mikey had already tossed the sharp tool in the air for the second time. He watched it soar until it landed safely in Mikey's lap. Leo, Raph and not to mention Mikey himself stared at the small knife in disbelief. No one dared to talk. It was like the Universe had looked away for a split second, and any sneeze or sound would make it realize what just had happened behind its back. Mikey eventually snapped out of the trance and quickly grabbed the tool with both his hands.

"_Booyakasha_!" Mikey cheered, and held up the knife for everyone to see. "Who's got a knife? Michelangelo's got a knife! Boo- yeah! You thought I was gonna drop it, huh? Well, what's this thing I'm holding then? Man, that was _swee-heet_! Mikey saves the day!"

"… How come I'm not feeling like jumping around and celebrating yet?" Raph asked deadpan.

"Because you're tied up?" Leo suggested.

"I don't think that's it," Raph said, with an uncomfortable look at Mikey, who was making the chair spin round and round in a sort of improvised victory dance.

"Great toss, Mikey," Leo said in relief. "Now please stop spinning before you drop that knife too... Hurry up and cut the cable tie-"

The doors to the lab creaked, and Leo snapped his head towards the entrance. Donnie walked inside and carefully sealed the doors shut behind him. He wasn't talking on the t-phone anymore. Leo looked at Mikey just in time to see the freckled turtle swiftly hide the knife between his palms. Mikey proceeded by glancing at the ceiling, which apparently was his idea of an innocent look. Leo wished that he would stop it. Innocent Mikey looked guiltier than a fat cat in an empty fish bowl. Leo almost expected him to start whistling too, just to add to the act. Raph on the other hand was pretending to be asleep again. Leo decided to not point out the fact that the hothead was finally following his advice. He knew why he was doing it. The memory of the antibiotics shot wouldn't go away any time soon. And he could tell that Raph's leg still hurt.

Leo turned back to Mikey with a panicky look, silently trying to scream to the younger turtle to stop acting so darn suspicious. But Mikey couldn't see Leo's insistent looks since he was too busy checking the ceiling for rain clouds. Leo glanced in Donnie's direction, but to his great surprise, the tall turtle didn't as much as look at his brothers. Donnie's eyes were fixed on something in the distance that Leo couldn't see, and he walked right past them. As if they had been part of the room's interiors. Leo watched Donnie with a raised eyebrow as the scientist went over to the cluttered working desk.

"… You okay there, Donnie?" Leo inquired uncertainly.

Donnie didn't respond. Leo observed his brother's every movement. Trying to read him the same way he'd been taught to read an opponent in battle. Something was off about him. The way he slumped down in his chair, the look in his eyes when he almost automatically reached for some glass slides… His body language was more passive than Leo remembered. And he wasn't smiling anymore. Leo couldn't tell whether this was a good thing or not.

"So…" Leo started, while carefully observing his brother. "You've been on the phone for quite a while, Don. How was April-"

"She's studying with Casey," Donnie answered, and reached for a vial of Leo's blood.

He used the pipette to add some of the blood on the glass slide. There was a cold professionalism in his manner, from the way he handled his brother's blood to the way he put the slide under the microscope. But instead of examining it, he tapped his chin with a pondering look. "Well… One of them is studying and one is tutoring, I suppose. Apparently, they have a math test tomorrow and Mr 'Too cool for school' hasn't read that particular chapter yet. Or opened that particular book…"

"Oh," Leo said, as he watched Donnie return his attention to the blood sample. Leo had no idea what exactly Donnie was feeling right now. And by the looks of it, neither did Donnie. "I'm… Sorry to hear that."

"Don't be," Donnie told him indifferently, and removed the glass slide. "I explained the situation to her, and she volunteered to help me with this. She just doesn't have time to come over right away. But she sounded very excited about it."

"… Donnie, did you really explain the _whole_ situation to her?" Leo wanted to know.

Donnie looked up from the microscope in surprise at the question. He studied Leo for a second, as if he was a crossword puzzle with two possible answers. "… Your tone kinda implies that you think I lied to her."

Leo didn't say anything and just gave Donnie a deadpan look. Donnie frowned at him. "Are you serious? That's what you think of me? Come on… Why would I even do that? April is probably the only one here, you know, except from _me_, who actually understands the importance of this research. I don't see any reason to why she wouldn't want to help me with this."

"So exactly what _did_ you tell her about your research?" Leo asked, with narrow eyes.

"Most of it," Donnie shared, and scratched his head. "Well, the broad spectrum of it anyway. I didn't wanna bore her with all the technical data and medical details. But I informed her about my progress and, more importantly, that I'll need samples of her DNA in order to speed up the process. I think she seemed rather happy to contribute to that part."

"Doesn't sound that way, considering that she preferred to stay with Casey," Leo pointed out, closely watching Donnie's reaction.

Leo knew that there were few subjects that could stir up Donnie's emotions as much as Casey Jones, and especially the subject of Casey Jones being alone together with a certain April O'Neil. He had seen the look in Donnie's eyes every time Raph joked about it, and under normal circumstances, Leo would never do this to his brother. But if they wanted to find out how far gone Donnie was, this was a good way to do it.

"Don't worry, she'll be here soon enough," Donnie simply stated as he picked up a glass slide to place under the microscope, only to realize that it was the same he just had removed. He gave the object a puzzled look before putting it away for a second time and reached for an empty beaker instead. "Though, I guess it all comes down to her priorities. Either she'll help me finish a cure for everyone who has been mutated in New York, which includes her own father, or she'll stay topside and help Casey barely pass math. And I think we all know that only one of those options is actually achievable."

Donnie made an amused small chuckle at this, and Leo couldn't hear any indication that he was faking it. Donnie sounded truly unfazed over the thought of April helping Casey with his studies. Leo just stared at his brother. This was not the reaction he had expected. And it scared him. He watched how Donnie mixed some different components in the beaker, apparently attempting to make a new batch of retro-mutagen. Leo took a deep, calming breath. _Mikey has the knife_, he reminded himself. More importantly, Donnie didn't _know_ that Mikey had the knife. They had an advantage. All they needed now was an opportunity to use it.

"Has Raph moved at all while I was gone?" Donnie suddenly asked, with a curious look at the turtle on the cot.

"Nope!" Leo quickly answered, with great conviction. "Just… Sleeping like a clobbered baby. I wouldn't wake him if I were you. He might get cranky…"

"I wasn't planning to," Donnie answered sincerely, as he stirred some kind of powder into the mixture. "Since I don't know what kind of anesthesia I used to knock him out, I have no idea what I would use to wake him up. I could try, but there's a real possibility that it would just make him worse… Plus, I'm actually kinda enjoying the absence of threats and insults for a change. I find it relaxing."

"… May I ask you something?" Leo asked, with a wary look at the scientist. "When you were talking to April, did you happen to mention me, Raph or Mikey? Like, at all?"

This made Donnie look up as he was in the middle of adding some pink liquid to the concoction. He put away the flask with an apologetic look at Leo. "Did you guys want to say hi…?"

"Forget it", Leo said, in frustration. "Did she say when she'd be here?"

"Not really," Donnie answered with a shrug, and went back to his experiment. The pink liquid made the solution turn bright yellow as he stirred it into the mixture. "She said that she'd come here when they're done studying, so… Soon, I hope."

Donnie observed the yellow mixture with a pleased look and picked up a petri dish from a drawer. He swiftly added another sample of Leo's blood on it before using the pipette to draw a small amount of the attempted retro-mutagen. He watched it closely as he carefully applied one tiny, bright yellow drop to the blood sample. There was a frizzing sound, like water hitting a hotplate, and the petri dish instantly cracked from the contact. Donnie watched the pieces with a blank expression and then sighed.

"… Very soon I hope," Donnie said, with a dejected look. He then brushed away the tiny pieces of plastic and got up from his chair. "I'm just wasting time and samples on this. It's like trying to mix green paint without the color blue. It's not just tedious, it's flat-out impossible…! I think I better put these tests on a hold for now, at least until I can get some samples from her. Maybe I could…"

Donnie glanced at Mikey, and raised an eyebrow. "What's up with Mikey?"

The uncharacteristically quiet turtle quickly hid the knife which he had been using to saw through the cable ties around his wrists. He hadn't spoken during the whole time and had focused solely on trying to cut himself free whenever his brother wasn't looking. He must have been extremely careful, since not even Leo had realized what he'd been doing. Donnie's sudden remark made the young turtle freeze in his seat, fearing that the slightest of movement would tell the scientist exactly what his specimen had been up to behind his back. Mikey swallowed nervously and kept his palms tightly together to conceal the weapon while Donnie examined him from the desk.

"What does that look mean? I don't get it," Donnie asked, with narrow eyes. "… You seem a bit pale. Are you trying to tell me that you're feeling ill? Do you need a bucket?"

"Um…" Mikey hesitated. He glanced at Leo, but the leader's insistent headshakes weren't of much help. Mikey gave Donnie an uncertain look. "Do… you still have that lollipop? 'Cause I kinda want it now."

"I don't think that would be such a good idea," Donnie stated vaguely, and got up from his chair, but then turned to Mikey with a reassuring smile. "_But_ you can have one right after we're done."

"Sweet!" Mikey said with glee before his expression quickly changed into a puzzled one. "Wait… Done with what?"

Donnie left the desk without answering Mikey. The freckled turtle tilted his head in confusion when Donnie passed him. Leo could feel his heart skip a beat when he watched the tall turtle head towards the water tanks.

"Donnie…?" Leo said slowly, his eyes fixed on his brother.

Donnie either couldn't hear him or didn't find it necessary to reply. There was an eerie tension in the room similar to that of an oncoming thunderstorm, and Raph carefully opened one eye to see what was going on. He snapped both eyes wide open when he saw Donnie at the tank, untangling the very same chains he recently had freed Raph from. The red masked turtle stared at the scene. He looked as if someone had replaced every drop of blood in his veins with ice water.

Donnie made one last check to make sure that the chains and the hook to the winch were in order. He then turned to his youngest brother with an excited smile that seemed more than just mildly inappropriate. "Alright, your turn now, Mikey."

"What do you mean with my turn?" Mikey asked, with a worried expression that quickly escalated to a look of panic when Donnie approached him. "W-W-Wait, WAIT! I don't wanna go anywhere, I like it here! I've made myself at home, I don't wanna move, I don't- Hey, hey, hey- No! NO! QUIT IT!"

Donnie had untied the already loose cable cord around Mikey and promptly hoisted him down from the chair. Mikey landed on the floor with a pained sound, unable to break his fall with his hands still tied together. Before he could protest, Donnie had already grabbed him under the armpits and started dragging him across the floor towards the tanks.

"No, Donnie…! What are you gonna do to him! Donnie? DONNIE!" Leo yelled. The image in his head already held the answer to that, but Leo didn't want to think of it. He didn't want to see it. "_Wait_! Tell me that you're not gonna do anything to him! Hey, I'm talking to y- _Donnie, just answer me_!"

"… Do you _have_ to be that loud?" Donnie asked, with a strained voice, as Mikey wasn't about to let his relocation go smoothly and thus kicked and squirmed as much as his restrained limbs allowed him to. "I figured… Mikey, stop that… Well, since we're basically just sitting around on our butts waiting for April, I could use the time to actually get some work done. And preferably without wasting all my blood samples and petri dishes…So I thought I might just as well continue my research about our lung capacity and if the properties of our mutation allow us to absorb oxygen directly from the water-"

"But you already did that!" Leo interrupted urgently. "On Raph! Remember?"

"You know, the only reason to remind someone of events that happened less than two hours ago would be to check if the person suffers from brain damage," Donnie pointed out, with a tired look. "My memory is fine, thank you very much. And I'm guessing that you haven't conducted many scientific studies before, am I right?"

"He's not a scientific study! He's your brother! OUR brother!" Leo yelled so loud that it felt like his voice was going to rip his throat apart.

"Look, in order to get as accurate results as possible, I'm gonna need at least one more test subject so that I can compare the results," Donnie explained calmly, and stopped dragging Mikey for a moment to focus on the discussion. "I can't base an entire research on one single being's physiology. That would be absurd…! And not to mention incredibly inefficient…I might just as well throw my notes in the paper bin, and that wouldn't be fair to Raph, now would it?"

"_You think I care about that_?!" Raph suddenly shouted. His eyes were focused on Donnie like bullets on a target, and they were set on nothing less than murder. "You're _not_ putting Mikey in that thing too! Do you get that? You are NOT!"

"Hey, Raph's awake!" Donnie announced, with the brightest of smiles at the apparently not so sleeping turtle. "I'll check on you in a sec, buddy. I just got to- OUCH!"

Donnie let go off Mikey quicker than if the younger turtle had been covered in spikes, and took a few steps back. He stopped and stared at his left hand. There was a trail of blood running down his two fingers, causing crimson beads to roll down his fingertips and hit the floor in various patterns. The blood came from a fresh cut straight over his knuckles, and it was bleeding freely.

Donnie looked up from the wound and eyed Mikey in disbelief. The freckled turtle was sitting on the floor just a few feet away, holding the tiny knife with both hands in a deathgrip while pointing it directly at Donnie. His wrists and ankles were still tied together, but the lack of mobility didn't seem to concern him remotely. His hands were shaking but his eyes were determined. He glared at Donnie with the attitude of a small dog who knew that despite its size, it could still bite. He couldn't stand up, but at least Donnie couldn't come any closer either.

"Mikey…! What did you do that for?" Donnie scolded him. He swiftly removed the bindings from his right hand to apply them on the cut in an attempt to stop the bleeding. "… Ow. Man, that's not just a paper cut either… Where did you even get that thing?"

"It's standard equipment," Mikey answered, with a stubborn look.

"Here. Give it to me," Donnie sighed, and stretched out his uninjured hand. "You can't move your hands or feet, you'll end up hurting yourself-"

Mikey immediately sliced the air in front of him, making Donnie flinch away from the weapon. He watched Mikey in confusion, similar to someone who just had been attacked by his favorite pet. It was like he had a hard time comprehending the situation. "Mikey, put that away…"

"No!"

"It's okay, it's okay. Everything's just fine," Donnie said reassuringly. His voice was frightfully convincing, and nothing in his manner indicated that he wanted anything but to help his little brother. "You have the knife. No one's forcing you to do anything. You're in control now, see? Does that make you feel better…? I'm not gonna hurt you, Mikey. We're just talking. That's okay, right?"

Leo could have sworn that he had heard parts of Donnie's speech from a cop movie he had seen the other day. Ha also noticed how Donnie was slowly putting himself between Mikey and the exit. Effectively cutting him off from his only escape.

"You want to use that to free yourself, don't you?" Donnie asked, with an understanding nod. "Is that what you wanna do? It's alright. I won't stop you. I'll wait until you're done."

Leo and Raph stared at Donnie as if they had misheard him, and Mikey frowned. Donnie put his hands in his pockets and waited patiently. He gave the younger turtle an encouraging smile while tapping his foot to a tune only he seemed to hear.

Even Mikey could sense the trap in this, but he couldn't see where it was. He glanced at the knife in his hands and at the cable ties that forced his feet together, just like his wrists. He glanced at Donatello again with an uncomfortable look. Donnie was trying to make Mikey point the knife away from him. The moment Mikey tried to cut himself free, there was nothing keeping Donnie away from him anymore. A pressure point, a swift hit to the neck, or a kick in the side… Two seconds was all it took for Donnie to be back in charge.

They were stuck in a stalemate. Donnie gave the younger turtle a puzzled look "… Is this you acting out just because I wouldn't give you that lollipop?" Donnie asked with a raised eyebrow, and seemed to honestly consider this as a valid reason for Mikey's sudden strange behavior. "Hey, how about this?" He continued, and started digging for something in his pocket before picking up a lime green lollipop. "If you give me the knife, I'll give you this. Eh? What do you say?"

Mikey blinked for a second before glancing at his remaining sane brothers. "Um… Guys? Any suggestions…?"

"Don't take the candy!" Leo told him.

"Dude, really…?" Mikey asked him, with an offended look.

"Forget that! Mikey, stab him!" Raph interrupted.

"Wow… You guys are a tremendous help," Donnie said, with a stern look at his brothers. "I'm trying my best to calm him down here, and you guys are just freaking him out!"

"… I don't think that's us," Leo stated.

"Come on now, Mikey," Donnie sighed impatiently, as if he was running late for an important business meeting. "Stop waving that thing around, it's sharp. Can't you see what you're doing? You're acting like a crazy person."

"Takes one to see one!" Mikey retorted, but then paused. "Wait… Let me try that again."

"Just give it to me before you cut up an artery or something worse," Donnie stated, and took a step closer, but stopped when Mikey made a stabbing motion, warning him to come any closer. Donnie raised an eyebrow. "Really? I'm asking for your help, and this is your response? To point a freaking knife at my face? Seriously, what's gotten into you lately? You used to like helping me in the lab."

"I liked helping _Donnie_," Mikey clarified, and glared at the other turtle.

"That doesn't even make sense," Donnie replied as he studied Mikey with a pondering look. "… Are you feeling feverish? It's possible that a rise in temperature could cause some of your behavioral symptoms… Here, let me check your-"

Donnie raised his hand, but quickly retracted it when Mikey once again swung the knife at him. The scientist made an exasperated gesture. "Listen, I don't think I have to tell you that I'm on a pretty tight schedule here. So are you planning on fussing like this until half of the population gets mutated, or should I just go ahead and ask the Kraang to postpone this whole invasion-thingy until you stop acting like a stubborn baby?"

Mikey gave him his best impression of an uncooperative four-year old, which made Donnie roll his eyes. "Alright, Mikey… Please tell me what I have to do to make you drop the knife."

The question made Mikey stop his act in surprise, as if it hadn't occurred to him that this was a possible outcome. His face was blank as a check, but then turned into a persistent look. "You have to let Raph and Leo go! I'll give you the knife if you let them leave first."

"I can't do that," Donnie stated in a matter of fact voice. He calmly put the lollipop back in his pocket, and noticed the improvised bandage on his left hand. It had bled through a little. Donnie turned the bloody fingers over, as if to study them from another angle. His face was hard to read. "Well, I guess this makes us even…" Donnie mumbled, with a strangely unconcerned look at the injury.

"How…?" Mikey asked uncertainly, and watched his brother as if he was a ticking gift box covered in wires.

The question was met with a suspicious glance from Donnie. He then started to slowly circle Mikey, eying every inch of him carefully. The orange masked turtle had some difficulties following him with the knife and had to turn his head almost all the way around in order to not lose sight of him.

"You know…" Donnie eventually said, folding his arms with a calculating look. "Without the element of surprise, I don't see how you could possibly fatally injure me with that thing. It's too short to impale any of my internal organs, and considering the width of that blade, it's highly unlikely that it will cause any serious damage even if you do manage to get a hit."

"Of course he's saying that!" Raph yelled, and gave Donnie a glare. "Don't listen to him, Mikey. He'll do anything to make you drop that knife."

"Actually, I'm just trying to be accurate," Donnie pointed out politely. "The success rate of a lethal hit depends on factors such as radial velocity, the mass of the blade, and the size of the initial impact. And I'm sorry to say that none of those seem to be in Mikey's favor at the moment." Donnie turned back to Mikey with a curious look. "Do you mind me asking where you were planning on aiming that thing? Because cutting aimlessly will most likely cause you to just hit a muscle. It will undoubtedly hurt, but not much else."

Donnie paused and tapped his chin with a contemplative look, too caught up in this chain of thoughts to notice Mikey's increasingly horrified look. "Severing an abdominal artery or vein would probably cause me to collapse on the spot, though. But you'd need a _way_ heavier blade for that. In your situation, I think the femoral artery would be the most efficient place. In that case, you should try and aim for the upper spot behind my knee. Or you could always go for my eye sockets, that way you could even cause direct damage to my brain. But keep in mind that those kinds of injuries, no matter how gruesome they may sound like, don't necessarily incapacitate someone. You could also cut open my jugular vein, in which case I'd be dead in a matter of minutes. I'd probably pass out from an air embolism before I actually bleed to death, but it should do the trick just the same, right?"

Mikey stared at the scientist, like a kid that just had been instructed to dissect a frog. It was as if every word Donnie spoke was nailed to his mind in the form of graphic pictures. Donnie stopped for a moment and studied Mikey's expression before giving him a kind smile. He crouched down only inches away from the knife, which made Mikey recoil with a terrified look. Donnie didn't say anything and just observed him in sympathy.

"I don't think you have it in you, buddy," Donnie told his little brother with a soothing voice, apparently meant to cheer him up.

"… Well, you're right about that," Mikey answered in a low voice as his expression slowly changed, like a cloud moving in over the sun. Donnie blinked in surprise when Mikey suddenly laid down flat on his back and lunged his feet at him, kicking him right in the chest. The power of the two foot kick was comparable to a small catapult hurling a large piece of solid rock. There was a cracking sound from the impact that immediately sent Donnie flying and crash to the ground a couple of feet away. Mikey didn't stop to check the devastating outcome of his attack, and quickly used the knife to saw through the cable ties around his ankles. Three seconds later, his feet were free and he skillfully jumped up from the floor. He looked at his tied up wrists. The hands were gonna be trickier.

Mikey decided to make a run for the lab doors instead, but stopped almost immediately. Donnie was already getting up from the floor. The taller turtle was gasping slightly for air, but other than that he seemed fine. Mikey looked at the exit, but didn't move.

"What is he waiting for?" Raph asked Leo, his voice filled with panic. "Come on, Mikey! RUN FOR IT!"

"He can't get to the door without passing Donnie," Leo explained, with a worried look. "And Donnie's back on his feet now…"

Leo was right. Donnie had recovered from the attack and was now standing up, one hand clutching his chest with a pained expression. Mikey took one look at him and then dashed in the opposite direction instead. Right towards his brothers.

"Mikey, no! You don't have time to free me," Leo yelled when the younger turtle ran up to him. "It's no use! I can barely walk…! Try the garage door, or go for the-"

Leo went quiet as he felt Mikey slip something underneath his left palm. Mikey then reached for the button on one of Leo's seatbelts, but something swiped the young turtle's legs before he could even touch it. Mikey landed hard on his stomach, the sudden impact making him bite his tongue. Mikey cringed in anguish with a dazed look while Donnie went over to Raph's bed and casually leaned his bō staff against it. The taller turtle studied the smaller one for a moment and then hurried over to the water tank. He was back in a matter of seconds with the heavy chains in his arms. Mikey groaned when Donnie sat down on his back and started to tie his little brother's arms and legs together.

"Geez… What were you thinking?" Donnie scolded Mikey, in the semi-angry voice of a worried parent. "You can't run around with a knife like that, you could trip and stick an eye out! And those things don't grow back, you know."

"How about ribs…?" Mikey asked in a pained voice. "I think I heard something break…"

"That makes two of us…" Donnie muttered, and tightened the chains around Mikey's body, making the younger turtle squirm in discomfort. "… Aaand that should do it. Assuming that you're not hiding an electric hand saw too, I think we're ready to pick up where we left off."

Donnie hesitated for a second and glanced at his work desk. The hand saw he had used on Leo earlier were lying on the messy table among some blood vials and notes, forgotten and maybe a little lonely. Donnie eyed it for a moment, as if he was trying to recall something but then shrugged and returned his attention to Mikey. "Let's not waste any more time, alright? The sooner we start, the sooner it will be over. Okay, here we go…"

Donnie started dragging Mikey's body over the floor, but halfway to the water tanks, he suddenly stopped. He looked down at Mikey with a raised eyebrow. "Where's the knife?"

Leo swallowed nervously. He could feel the small piece of metal under his hand. It felt like it was screaming out its location to anyone who wanted to hear. Mikey hadn't been free for very long. Even Donnie's messed up mind would figure out where that knife had gone to.

Mikey looked at Donnie with a blank expression before looking down at his hands. The chains around his arms and body prevented him from moving, but in his right hand he was clutching a tiny throwing knife. Leo recognized it as the first one that Mikey had dropped. When did he get the chance to pick it up?

Donnie relieved him from the small weapon and put it in one of his lab coat's many pockets. "I better hold on to this," he reasoned. "I don't want you to hurt yourself during the procedure. There's no telling how your body will react once submerged, and I think it would be safer for you if you didn't have any sharp objects on your person. Raph wasn't exactly what you would call 'calm' when I did this to him…"

Leo could see Raph shudder on the cot, and he had a feeling that it wasn't because he was cold. Donnie then grabbed the loose end of the chain and started pulling Mikey with him, similar to someone returning home after a successful hunt. Mikey tried to dig his heels into the floor in a desperate attempt to slow down his capturer, but it was as useful as an anchor made out of floaties.

Watching Donnie pull Mikey further and further away made Leo's skin crawl. His breathing had quickened, but Leo barely noticed it. He was too occupied trying to force his brain to cooperate. He had to come up with a plan. Mikey was unarmed. He couldn't free himself this time, so they had to help him. And they had to help him _now_. But how? All he had was the knife Mikey gave him. One knife, but no ideas.

Mikey carefully turned his head to Donnie. He studied the taller turtle for a second and made a nervous laugh. "… Okay, I totally get it now. You guys are all in on this, am I right? I knew it. I _knew_ that blood looked fake…! Ha, ha! Man, you totally had me there… This is payback for that time I switched your toothbrushes, huh? Or the time I stuffed Raph's pillow with worms. Or put hot sauce and pepper on Leo's pizza. Okay, I admit it. I deserved this. I'll try to hold back from now on. No more water balloons. Well, no big ones, anyway… Prankster's promise. Heh. So, um… Why are you still dragging me…?"

Donnie didn't answer. It was almost as if he was too far away to hear him. Leo didn't know what was going on inside Mikey's head right now, but he had an idea. He had known his little brother long enough to know that Mikey had a somewhat different view on the world than the rest of them. He was naïve to a fault, always thinking the best of people. And that's what usually got him into trouble. He could learn to not trust enemies. But accepting the fact that his own brother could possibly put him in mortal danger…? Leo could barely comprehend it himself. It was no wonder that Mikey rather chose to believe that it was all part of a horrible joke instead of a horrible reality.

They were almost at the winch now, and Mikey's smile faded the closer they got. "Bro, snap out of it…" Mikey whispered. His big eyes darted back and forth between Donnie's back and the water tank. "Okay, you're being super scary right now… And not zombie-robot-monster-scary, I mean _really_ scary. Could you please stop it? Like, now…? Or now? This isn't funny anymore, Donnie. It never was…!"

Mikey desperately tugged at the restraints, like cat in a leash, but Donnie held his end of the chain in a firm grip and didn't even slow down.

"Look, I'm sorry, okay!" Mikey cried out, and looked up at Donnie. "I'm sorry I tried to run away, I'm sorry I cut your hand, it was an accident, and I'm sorry I kicked you in the chest, I'm sorry for everything I ever did…! I will never do anything for as long as I live if you just let me go, _please let me go_!"

"_Mikey_!" Raph yelled, but this time it wasn't in anger. His eyes were filled with dread as he watched Mikey struggle, and he turned to Leo with a frantic look. "Think of something, Leo! You can't let him do this to him! Not to Mikey…!"

"I can't even move, and Donnie stopped listen to me a long time ago! What else am I supposed to do?!" Leo replied in distress, and watched as Donnie moved away from them. "Donnie! Please hear me out this time… You _have_ to stop this before you- Please, Donatello…! Stop, JUST STOP!"

But Donnie didn't stop. He made one last pull and left Mikey right next to the tank. The freckled turtle's eyes stared at the greenish blue algae water. He shook his head in protest and squirmed at the restraints. "I don't wanna drown... Please, Donnie, I really don't wanna drown. You're not really gonna do it, are you? Right? Please, please, please, please… I don't wanna drown! I don't wanna drown! I DON'T WANNA-"

"_Stop_ _screaming_, please," Donnie begged, and closed his eyes with a pained sigh before turning to Mikey. "You're _not_ going to drown. Do you really think I'd do that to you?"

"You did it to Raph!"

"And he's fine. See? I'll make sure you'll be too," Donnie said, with a reassuring smile and made an attempt to pat Mikey, but the younger turtle pulled away from him. Donnie tilted his head in a curious manner and put his hand in his pocket instead. "You'll be fine. Just trust me on this. I would never let anything happen to any of you guys."

Mikey looked at Raph and Leo's direction and swallowed uncomfortably. Donnie noticed his little brother's inaudible criticism and scratched his neck. "… Well, naturally I'm not counting certain unexpected turns of events and unavoidable calamities. But let's not dwell on that. Dynamite wasn't invented without a few lost fingers. Now let's see…"

Donnie picked up the hook from the floor and started fiddling with the chains in order to attach it properly. "The hook goes here and... Great! Okay, down you go."

"No, no, no, NO!" Mikey protested as Donnie left him to start the machine. "Don't do this, Donnie. I don't wanna go into the water tank… I don't wanna die!"

"… You're really that scared, Mikey?" Donnie suddenly asked, with a surprised eyebrow at his youngest brother. "You really think that you're gonna die?"

Mikey nodded intensively with an urgent look at the scientist. Donnie's shoulders slumped a little with a concerned look. "Aw, buddy… You have nothing to worry about," Donnie told him and crouched down next to Mikey. "Now, listen. Just because something may seem really scary doesn't mean it's dangerous. I'm _just_ gonna compare your ability to sustain yourself under water with the data I got from Raph. It's the exact same thing he did," Donnie explained with a smile and put a hand on Mikey's shoulder. "With the minor difference that you will be in there somewhat longer. It's not that big of a deal, really."

"Not a big deal?!" Leo yelled from his spot. "Raph stopped _breathing_!"

"I fail see how that's relevant," Donnie stated, and scratched his chin. "Considering that in Raph's case, it was caused by unforeseen complications due to the drug-"

"Mikey could still drown…!"

"And I don't wanna drown!" Mikey pleaded. He was breathing in short, rapid breaths now. Every inhale he made was rushed, as a desperate attempt to suck down oxygen into his lungs, but he barely allowed himself to expel the collected air. The high pitched sounds from Mikey's breathing caught Donnie's attention, and he studied the freckled turtle closely. He then looked at Leo in a tired manner. "Well, congratulations. Now he's hyperventilating again. You do realize that this could severely diminish his ability to sustain himself under water, right?"

"Then let me take his place!" Leo said, with an insistent look at his brother. "I mean it! Use me instead!"

"I _can't_," Donnie stated, and shook his head. "You have lost too much blood, so the risk of a mortal outcome in your case exceeds my 48,9 limit. But don't worry. You'll get your turn when I'm certain that you're strong enough to make it."

Before Leo could protest, Donnie had flipped the switch and started the winch. Mikey's eyes were the size of teacups as he watched his feet slowly leave the safe surface of the floor. Donnie let the steel wire pull Mikey up from the ground until the young turtle was dangling helplessly in the air. He then went over to Mikey and moved his hanging body until it was swaying right above the green water surface.

Leo's mind was in a deadlock. He had tried fighting. He had tried yelling. His muscles hurt and his throat was sore from all the screaming... What else could he do? He could hear Raph struggle against his belts with the ferocity and determination of a fettered animal, but Leo felt paralyzed.

Donnie turned the lever to set the machine in reverse, allowing the metal wire to lower Mikey's body closer to the water. Mikey flinched when his toes suddenly touched the surface and quickly tried to pull up his knees. But his effort didn't stop the winch from mercilessly sending his legs down into the water. Mikey shuddered and glanced at Donnie with a pleading look. "I-I-It's r-really- _really_ c-c-cold, Donnie… Ca-Can you at least h-h-heat the water f-f-f-first…?"

"I'm sorry, Mikey," Donnie said, with a sad headshake. "The temperature has to be as low as possible to slow down your heart rate and simulate the conditions under where a turtle goes into hibernation."

"We don't hibernate, Donnie…!" Leo pointed out, with a stern look.

"What we _know_ of," Donnie corrected him as he suddenly turned off the machine. The water was reaching Mikey's chin now, and he had to stretch his neck in order to keep his mouth above the surface. Donnie crouched down at the edge of the tank with an excited look that completely clashed with Mikey's terrified one.

"We're almost done. I just need to go through a few details with you before we continue, alright?" Donnie explained to him. "First of all: Just so you know, I'm going to set the timer on 30 minutes." Donnie paused in realization. "… Which means that you're probably gonna beat Raph's record. Hey, isn't that cool?"

"I don't wanna beat Raph's record…!" Mikey protested, and started to tug at the chains again. He was moving enough to cause the water to ripple and splash everywhere. Mikey coughed as some algae water made its way down his windpipe, but it didn't stop him from struggling. It didn't work, but the panic that was growing inside of him didn't care about that.

"Mikey, calm down- Hey, hey…! Mikey!" Donnie said, and firmly grabbed Mikey's shoulder to keep him still for a moment. "Calm down. Everything will be fine if you just listen to me. You can't panic like that when you're under water, it's dangerous. I need you to relax, do you understand? Here, I'm gonna talk you through this. Look at me, try and breathe like this," Donnie instructed and demonstrated by inhaling through his nose and then slowly exhale through his mouth. He repeated the act two times and then gave Mikey an encouraging look. "See? Do you think you can you do that? Try it now. Slow, deep breaths… Just like I showed you."

Mikey tried to follow Donnie's advice and breathed through his nose. He did this for a minute while Donnie nodded to him to keep going. "Good, that's very good. Okay, keep that up. I think we're all set now."

Donnie went back to the winch and was just about to hit the switch again, but then hesitated. He looked up with an almost dazed expression, as if he was struck by a thought that refused to leave him alone. He didn't move for a while, but eventually turned to Mikey again. "And by the way… Once you're fully submerged, if you could try to take water in your mouth and expel it through your nose, like this, that would be great. I want to check a theory I have on buccopharyngeal breathing."

Mikey turned his head to his other brothers. The bright blue color in his eyes was dimmed by fear. "You're not gonna let him do it, right guys…? You have a plan. A great one! I know you do! … Please say that you have a plan?" Mikey asked in a thick voice before giving the winch a look of absolute horror when Donnie flicked the switch. "No, no, NO WAIT…! Guys, please do something already! I don't wanna play anymore, I don't wanna do this… Please, Leo! Leo, tell him to stop! Please, help me…! Raph, help! RAPH!"

"Take a deep breath," Donnie instructed with a voice that was disturbingly unfazed by his little brother's cries. Mikey was breathing rapidly again, but obediently inhaled as much air as he could. He closed his eyes tightly when the sea green water hit his face and soon covered him completely.

Leo couldn't think. Mikey was in the tank, and Leo couldn't do anything. Mikey was in the tank. He couldn't get up, he couldn't breathe. Mikey was in the tank…! Leo's mind was swimming in panic stricken thoughts. It felt like they were going to engulf him. Eat him alive. He almost didn't hear the increasing growling noise coming from the cot. There was a sudden sound of a belt snap and Leo turned his head to his fellow captive. One of the cam-buckle belts were hanging from Raph's bed like a dead snake. Leo gaped at the sight as Raph, with a strength that no normal person should possess, was stretching the straps to their limits. He gritted his teeth, almost crushing them in the process, and his eyes were white with a rage that would not have recognized family or foe.

Donnie looked up at the sudden noise but quickly took several steps back. He stared at Raph in a mixture of alarm and amazement. "Sweet mother of all mutations...!"

Another belt gave in to the brutal force from the turtle. Raph's muscles were so tensed up that a dagger wouldn't been able to penetrate them. He closed his eyes with a determined look before making another tug at the belts. A third one was ripped apart and fell to the floor in defeat. Now there were only two left.

"Okay, not good… Raph? Raph!" Donnie called out, and hurried over to him. "Listen, you _don't_ wanna do this. Trust me, or at least listen to me... I really mean it. Don't-"

Donnie reached for his staff next to Raph's bed, but recoiled when the last two belts burst in succession after a furious roar from the red masked turtle. Donnie backed away and stared at his freed brother like a rabbit about to be hit by a speeding truck. This was the first time today that Leo had seen Donnie showing something that even remotely reminded of fear.

Raph got up on all four and was panting heavily. His breathing was strained and you could almost see steam coming out of his nostrils with every exhale. Nothing was stopping him from leaving the cot, but yet he wasn't moving. Raph legs and arms were trembling slightly and he started swaying a little where he stood, fighting to stay up straight. His face changed into an anguished one moments before he crashed down on the bed again. Evidently, the little strength he had left wasn't enough to keep him up. Donnie walked up to him carefully before putting a hand on his back.

"… Yeah, that's what I suspected," Donnie said, and studied his fallen brother with a sympathetic look. "You really don't want me to do this to him, do you?"

Raph's breathing was ragged and he could barely glance at Donnie in reply. The hothead's eyes were narrow and filled with detest. Donnie only nodded, as if they were having a deep conversation and Raph had made a very compelling argument. "Don't worry, pal," Donnie said, with his best bedside manner. "I already told you: I won't let anything happen to him. It's completely harmless. You know that."

Raph closed his eyes, too tired to object. Donnie studied the silent turtle for a moment before reaching for something in his pocket. "I need you to lie still while I get you some new belts. It's okay. I'll be back in a jiffy. I'm just gonna give you something first…" Donnie explained calmly. "I think you'll recognize it."

Leo expected another lollipop with yet a new color, but felt his stomach turn when Donnie picked up a needle and a small bottle. Donnie started to fill the syringe, with the swiftness of someone who'd had a lot of practice. He tapped it a few times when he was done, and Raph made a weak attempt get up, but Donnie gently pushed him down on the bed again.

"What are you doing now? What the heck's in that thing?" Leo wanted to know as he watched Donnie prod Raph's arm for a good spot.

"Nothing that he hasn't had before…" Donnie reassured him, but with no real interest in Leo's inquiry. He then pushed the sharp instrument through Raph's skin and injected the clear liquid, making the turtle cringe. "Just as a precaution. And I usually don't favor these side effects, but in this case I really think that Raph could benefit from some drowsiness. That stunt must have drained the life out of him… Hopefully, this will help him rest a bit."

Donnie retrieved the needle and rubbed his thumb over the puncture mark in a comforting way. Raph managed a warning snarl, and Donnie pulled away from him. He made a small, nervous chuckle at this and looked at the syringe. "You're getting quite acquainted with this stuff, aren't you? Lucky I grabbed this bottle in the last minute. It's been quite handy so far-"

The gleeful noise of someone getting a text interrupted Donnie, who quickly checked his phone. The smile that spread across his face was the spitting image of whenever Donatello got a text message from a certain red head. Only that this time, the smile was of a different kind.

"Please tell me that wasn't April…" Leo begged, but wasn't sure whom he was directing the question.

"Awesome!" Donnie declared, not showing any sign of having heard Leo's comment. He quickly sent a reply consisting of the same word and a smiley face, before putting the phone back in his pocket. He put his hands on his hips with a confident grin at his brothers. "Hey, guys. Guess which female acquaintance of ours that has decided to come over now and help me?"

"… A lady from social services?" Raph suggested, in a weaker voice than Leo had ever heard him. Leo knew that sarcasm was a compulsion for Raph, and didn't necessarily mean that he was trying to be funny. Especially when he only seconds ago had been injected with yet another drug.

"April," Donnie corrected, with a confused look at Raph as the joke was way over his head. He made a quick scanning of his surroundings and tapped his chin. "I better set up a few things before she gets here. Let's see… I'm gonna need a chair. Well, that's an easy fix, considering that Mikey isn't using his anymore… Oh, right!"

Donnie hurried over to his desk and picked up the egg timer, only to eye it hesitantly and look at Leo. "It seems like your next dose is up in about twenty minutes. You're gonna have to remind me so that I don't forget, okay?"

Leo felt it as if someone had stabbed him in the stomach. Mikey… For the first time, they literally had a deadline. Every second Mikey was under water was a failure from his side. Leo had no idea how long Mikey could hold his breath, and he didn't care how certain Donnie was that he was going to make it. Raph nearly died from being submerged for 20 minutes. Nothing good could come from Mikey doing the same for 30.

Donnie had started moving around some of the equipment on his table, either in a brave attempt to clean it up a bit, or to search for something specific. He then stopped what he was doing with an almost absentminded look. He slowly glanced at Raph and Leo.

"… You are gonna try to ruin this, aren't you?" Donnie asked, and studied them warily, like a teacher eying two well-known troublemakers.

"What…?" Leo asked, with a raised eyebrow.

"I know that it's just your idea of a joke, but April may not appreciate this _hilarious_ running gag you got going that I'm some sort of 'mad scientist'," Donnie explained with emphasizing air quotes, and started rummaging through one of his many drawers. "She could get upset and leave. I can't risk that, so therefore…"

Donnie picked up a roll of duct tape. Leo and Raph stared at their brother as he left the desk to approach them. "It's only temporary. And besides," Donnie continued and pulled out a piece, big enough to cover a mouth. ", you're not really leaving me much choice."

* * *

><p><strong>Next Time:<strong> Can April put an end to this madness?

Also: No Michelangelos will lose their lives in this fanfic.

_Fun Fact: The research for this chapter partly consisted of my sister tying my hands and feet together and put me in a revolving chair, just to see if I still could pick up a small object with my feet. As Mikey demonstrates, you can. The tricky part is to get the object from your feet to your hands. Knees just don't bend that way. Throwing it proved to be the only method that worked for me. And that's all from today's science class. _


End file.
